Summary of Pesticide Use Report Data - 2008

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Indexed by Chemical


CALIFORNIA DEPARTMENT OF PESTICIDE REGULATION
California Environmental Protection Agency
1001 I Street
Sacramento, California 95814-3510
Arnold Schwarzenegger, Governor
Linda S. Adams, Secretary for Environmental Protection
Mary-Ann Warmerdam, Director
Department of Pesticide Regulation
State Seal

November 2009

Any portion of this report may be reproduced for any but profit-making purposes. For information for obtaining electronic data files, see Page iii. This report is also available on DPR's Web site. If you have questions concerning this report, call (916) 445-3887.

TABLE OF CONTENTS

How To Access The Summary Of Pesticide Use Report Data

I.  INTRODUCTION

II.  COMMENTS AND CLARIFICATIONS OF DATA

III.  DATA SUMMARY

IV.  TRENDS IN USE IN CERTAIN PESTICIDE CATEGORIES

V.  TRENDS IN PESTICIDE USE IN CERTAIN COMMODITIES

VI.  SUMMARY OF PESTICIDE USE REPORT DATA 2008 INDEXED BY CHEMICAL (PDF, 1.8 mb)


How to Access the Summary of Pesticide Use Report Data

The Summary of Pesticide Use Report Data indexed by chemical or commodity reports for years 1989-2008 can be found on DPR’s Web site. The Summary of Pesticide Use Report Data is available in two formats. One report is indexed by chemical and lists the amount of each pesticide used, the commodity on which it was used, the number of agricultural applications, and the acres/units treated. The second report is indexed by commodity and lists the chemicals used, the number of agricultural applications, amount of pesticides used, and the acres/units treated.

The Annual Pesticide Use Report Data (the complete database of reported pesticide applications for 1990-2008) are available on CD ROM. The files are in text (comma delimited) format.

The complete PUR database (Zip files by year, 1974 to current year) may be downloaded from DPR’s FTP site .

Questions regarding the Summary of Pesticide Use Report Data should be directed to: Department of Pesticide Regulation, Pest Management and Licensing Branch, P.O. Box 4015, Sacramento, California 95812-4015.Telephone (916)445-3887 or e-mail to mwilliams@cdpr.ca.gov.


I. INTRODUCTION

Development and Implementation of the Pesticide Use Reporting System

This 2008 Summary of Pesticide Use Report Data includes agricultural applications and other selected uses reported in California. The report represents a summary of the data gathered under full use reporting. The Department of Pesticide Regulation (DPR) uses the data to help estimate dietary risk and to ensure compliance with clean air laws as well as ground water protection regulations. Site-specific use report data, combined with geographic data on endangered species habitats, also helps county agricultural commissioners resolve potential pesticide use conflicts. Detailed, individual pesticide use report (PUR) data may be obtained from DPR for in‑depth, analytical purposes.

Under full use reporting, which began in 1990, California became the first state to require reporting of all agricultural pesticide use, including amounts applied and types of crops or places (e.g., structures, roadsides) treated. Commercial applications–including structural fumigation, pest control, and turf applications–must also be reported. Pesticide use reporting is explained in more detail below.

Types of Pesticide Applications Reported

Partial reporting of agricultural pesticide use has been in place in California since at least the 1950s. Beginning in 1970, anyone who used restricted materials was required to file a pesticide use report with the county agricultural commissioner. The criteria established to designate a pesticide as a restricted material include potential hazard to:

  • public health
  • farm workers
  • domestic animals
  • honeybees
  • the environment
  • wildlife
  • other crops

With certain exceptions, restricted materials may be possessed or used only by, or under the supervision of, licensed or certified persons, and only in accordance with an annual permit issued by a county agricultural commissioner.

In addition, the State required commercial pest control operators1 to report all pesticides used, whether restricted or nonrestricted. These reports included information about the pesticide applied, when and where the application was made, and the crop involved if the application was in agriculture. The reports were entered into a computerized database and summarized by chemical and crop in annual reports.

With implementation of full use reporting in 1990, the following pesticide uses are required to be reported to the commissioner, who, in turn, reports the data to DPR:

  • For the production of any agricultural commodity, except livestock.
  • For the treatment of postharvest agricultural commodities.
  • For landscape maintenance in parks, golf courses, and cemeteries.
  • For roadside and railroad rights-of-way.
  • For poultry and fish production.
  • Any application of a restricted material.
  • Any application of a pesticide with the potential to pollute ground water (listed in section 6800 (b) of the California Code of Regulations, Title 3, Division 6, Chapter 4, Subchapter 1, Article 1) when used outdoors in industrial and institutional settings.
  • Any application by a licensed pest control operator.

The primary exceptions to the use reporting requirements are home and garden use and most industrial and institutional uses.


1 Pest control operators include those in the business of applying pesticides such as agricultural applicators, structural fumigators, and professional gardeners.

How Pesticide Data Are Used

DPR undertook the expansion of use reporting primarily in response to concerns of many individuals and groups, including government officials, scientists, farmers, legislators, and public interest groups. It was generally acknowledged that the system for estimating dietary exposure to pesticide residues did not provide sufficient data on which to make realistic assessments; this often resulted in overestimates of risk. Farm worker representatives were also asking for more information to determine exposure and potential risk to those who handle pesticides or who work in treated fields.

There are several key areas in which data generated by full use reporting are proving beneficial.

Risk Assessment

Without information on actual pesticide use, regulatory agencies conducting risk assessment assume all planted crop acreage is treated with many pesticides, even though most crops are treated with just a few chemicals. If the assumptions used by regulatory agencies are incorrect, regulators could make judgments on pesticide risks that are too cautious by several orders of magnitude, reducing the credibility of risk management decisions. The use report data, on the other hand, provides actual use data so DPR can better assess risk and make more realistic risk management decisions.

After the passage of the federal Food Quality Protection Act (FQPA) in 1996, complete pesticide use data became even more important to commodity groups in California and to the U.S. Environmental Protection Agency (U.S. EPA). FQPA contains a new food safety standard against which all pesticide tolerances must be measured. The increased interest in the state’s pesticide use data, especially for calculating percent crop treated, came at a time when DPR was increasing the efficiency with which it produced its annual report. DPR was able to provide up-to-date use data and summaries to commodity groups, University of California specialists, U.S. EPA programs, and other interested parties as they developed the necessary information for the reassessment of existing tolerances.

Worker Health and Safety

Under the pesticide regulations [section 6619 of the California Code of Regulations, Title 3, Division 6, Chapter 3, Subchapter 2, Article 1], pest control operators must give farmers a written notice after every pesticide application that includes the pesticide applied, the location of the application, the date and time the application was completed, and the reentry and preharvest intervals2. This notice gives the farmer accurate information to help keep workers from entering fields prematurely, and also lets the farmer know the earliest date a commodity can be harvested.

DPR’s Worker Health and Safety Branch also uses the data for worker exposure assessment as part of developing an overall risk characterization document. Use data help scientists estimate typical applications and how often pesticides are used.


2 A reentry interval is the time from which a pesticide application is made and when workers may enter a field. A preharvest interval is the time between an application and when a commodity can be harvested.

Public Health

The expanded reporting system provides DPR, the State Department of Public Health, and the Office of Environmental Health Hazard Assessment with more complete pesticide use data for evaluating possible human illness clusters in epidemiological studies.

Endangered Species

DPR works with the county agricultural commissioners to combine site-specific use report data with geographic information system--based data on locations of endangered species. The resulting database helps commissioners resolve potential conflicts over pesticide use where endangered species may occur. DPR and the commissioners can also examine patterns of pesticide use near habitats to determine the potential impact of proposed use limitations. With location-specific data on pesticide use, restrictions on use can be better designed to protect endangered species while still allowing necessary pest control.

Water Quality

Since 1983, DPR has had a program to work with the rice industry and the Central Valley Regional Water Quality Control Board to reduce contamination of surface water by rice pesticides. Using PUR data to help in pinpointing specific agricultural practices, more precise alternative use recommendations can be made to assure protection of surface water.

The Pesticide Contamination Prevention Act requires site-specific records to help track pesticide use in areas known to be susceptible to ground water contamination. Determinations can also be made from the records on whether a contaminated well is physically associated with agricultural practices. These records also provide data to help researchers determine why certain soil types are more prone to ground water contamination.

DPR placed certain pesticide products containing pyrethroids into reevaluation on August 31, 2006. The reevaluation is based on recent studies revealing the widespread presence of synthetic pyrethroid residues in the sediment of California waterways at levels toxic to an aquatic crustacean.

Air Quality

Many pesticide products contain volatile organic compounds (VOCs) that contribute to the formation of smog. DPR worked with the state Air Resources Board to put together a State Implementation Plan under the federal Clean Air Act to reduce emissions of all sources of VOCs, including pesticides, in nonattainment areas of the state. DPR’s contribution to the plan included accurate data on the amount of VOCs contained in pesticides and the ability to inventory the use of those pesticides through pesticide use reporting.

Beginning in January 2008, regulations went into effect to reduce emissions of VOCs from fumigant pesticides. To help DPR keep track of these smog-producing emissions, PURs are used to monitor fumigant use and methods of fumigant application. This information is then used to compare with targeted emission reduction goals designed to improve air quality.

Pest Management

The Department uses the PUR database to understand patterns and changes in pest management practices. This information can be used to determine possible alternatives to pesticides that are subject to regulatory actions and to help determine possible impacts of different regulatory actions on pest management.

The PUR is used to help meet the needs of FQPA, which requires pesticide use information for determining the appropriateness of pesticide residue tolerances. As part of this process many commodity groups have created crop profiles, which include information on the pest management practices and available options, both chemical and nonchemical. Pesticide use data is critical to developing these lists of practices and options.

The PUR data have been used to support and assess grant projects for a grant program conducted by DPR to develop, demonstrate, and implement reduced- risk pest management strategies from 1995 to 2003. The grants were temporarily suspended due to the statewide budget shortfall, but funds were reinstated in 2007, and the grant program is currently ongoing. The PUR data have been used in several other projects that build on work conducted in the almond and stonefruit industries. In these and other projects, the PUR data are used to address regional pesticide use patterns and environmental problems such as water and air quality. The data are also used to better understand current changes in pesticide use.

DPR has published general analyses of statewide pesticide use patterns and trends. The first analysis covered the years 1991 to 1995, and the second more detailed analysis covered 1991 to 1996. These analyses identified high-use pesticides, the crops to which those pesticides were applied, trends in use, and the pesticides most responsible for changes in use. In addition, since 1997, the annual Summary of Pesticide Use Report Data include summary trends of pesticides in several different categories such as carcinogens, reproductive toxins, and ground water contaminants.

Processor and Retailer Requirements

Food processors, produce packers, and retailers often require farmers to submit a complete history of pesticide use on crops. DPR’s use report form often satisfies this requirement.




II. COMMENTS AND CLARIFICATIONS OF DATA

The following comments and points should be taken into consideration when analyzing data contained in this report:

Terminology

The following terminology is used in this report:

Number of agricultural applications – Number of applications of pesticide products made to production agriculture.  More detailed information is given below under "Number of Applications."

Pounds applied – Number of pounds of an active ingredient.

Unit type – The amount listed in this column is one of the following:
A = Acreage
C = Cubic feet (of commodity treated)
K = Thousand cubic feet (of commodity treated)
P = Pounds (of commodity treated)
S = Square feet
T = Tons (of commodity treated)
U = Miscellaneous units (e.g., number of tractors, trees, tree holes, bins, etc.)

Commodity Codes

DPR’s pesticide product label database is used to cross-check data entries to determine if the product reported is registered for use on the reported commodity. The DPR label database uses a crop coding system based on crop names used by the U.S. EPA to prepare official label language. However, this system caused some problems until DPR modified it in the early 1990s to account for U.S. EPA’s grouping of certain crops under generic names. Problems occurred when the label language in the database called a crop by one name, and the use report used another. For example, a grower may have reported a pesticide use on "almonds," but the actual label on the pesticide product-coded into the database-stated the pesticide was to be used on "nuts." DPR modified the database to eliminate records being rejected as “errors” because the specific commodity listed on the use report is not on the label. A qualifier code is appended to the commodity code in the label database to designate a commodity not specifically listed on the label as a correct use. A qualifier code would be attached to the "almond" code when nuts are only listed on the label. This system greatly reduces the number of rejections.

Plants and commodities grown in greenhouse and nursery operations represented a challenge in use reporting because of their diversity. Six commodity groupings were suggested by industry in 1990 and incorporate terminology that are generally known and accepted. The six use reporting categories are: greenhouse-grown cut flowers or greens; outdoor-grown cut flowers or greens; greenhouse-grown plants in containers; outdoor-grown plants in container/field-grown plants; greenhouse-grown transplants/propagative material; and outdoor-grown transplants/propagative material.

Tomatoes and grapes were also separated into two categories because of public and processor interest in differentiating pesticide use. Tomatoes are assigned two codes to differentiate between fresh market and processing categories. One code was assigned to table grapes, which includes grapes grown for fresh market, raisins, canning, or juicing. A second code was assigned to wine grapes.

Unregistered Use

The report contains entries that reflect the use of a pesticide on a commodity for which the pesticide is not currently registered. This sometimes occurs because the original use report was in error, that is, either the pesticide or the commodity was inaccurately reported. DPR's computer program checks that the commodity is listed on the label, but nonetheless such errors appear in the PUR, possibly because of errors in the label database. Also, the validation program does not check whether the pesticide product was registered at the time of application. For example, parathion (ethyl parathion) is shown reported on crops after most uses were suspended in 1992. (These records are researched and corrected as time and resources allow.) DPR continues to implement methods that identify and reduce these types of reporting errors in future reports. Other instances may occur because by law, growers are sometimes allowed to use stock they have on hand of a pesticide product that has been withdrawn from the market by the manufacturer or suspended or canceled by regulatory authorities.

Other reporting "errors" may occur when a pesticide is applied directly to a site to control a particular pest, but is not applied directly to the crop in the field. A grower may use an herbicide to treat weeds on the edge of a field, a fumigant on bare soil prior to planting, or a rodenticide to treat rodent burrows. For example, reporting the use of the herbicide glyphosate on tomatoes – when it was actually applied to bare soil prior to planting the tomatoes – could be perceived to be an error. Although technically incorrect, recording the data as if the application were made directly to the commodity provides valuable crop usage information for DPR’s regulatory program.

Adjuvants

Data on spray adjuvants (including emulsifiers, wetting agents, foam suppressants, and other efficacy enhancers), not reported prior to full use reporting, are now included. Examples of these types of chemicals include the "alkyls" and some petroleum distillates. (Adjuvants are exempt from federal registration requirements, but must be registered as pesticides in California.)

Zero Pounds Applied

There are a few entries in this report in which the total pounds applied for certain active ingredients are displayed as zero. This is because the chemical (active ingredient) made up a very small percentage of the formulated product that was used. When these products are applied in extremely low quantities, the resulting value of the active ingredient is too low to register an amount.

Acres Treated

The summary information in this annual report cannot be used to determine the total number of acres of a crop. However, it can be used to determine the cumulative acres treated. The problem is that the same field can be treated more than once in a year with the same active ingredient. A similar problem occurs when the product used contains more than one active ingredient. (In any pesticide product, the active ingredient is the component that kills, or otherwise controls, target pests. A pesticide product is made up of one or more active ingredients, as well as one or more inert ingredients.) For example, if a 20-acre field is treated with a product that contains three different pesticide active ingredients, a use report is filed by the farmer correctly recording the application of a single pesticide product to 20 acres. However, in the summary tables, the three different active ingredients will each have recorded 20 acres treated. Adding these values results in a total of 60 acres as being treated instead of the 20 acres actually treated.

Number of Applications

The values for number of applications include only production agricultural applications. Applicators are required to submit one of two basic types of use reports, a production agricultural report or a monthly summary report. The production agricultural report must include information for each application. The monthly summary report, for all uses other than production agriculture, includes only monthly totals for all applications of pesticide product, site or commodity, and applicator. The total number of applications in the monthly summary reports is not consistently given so they are no longer included in the totals. In the annual PUR reports before 1997, each monthly summary record was counted as one application.

In the annual summary report by commodity, the total number of applications given for each commodity may not equal the sum of all applications of each active ingredient on that commodity. As explained above, some pesticide products contain more than one active ingredient. If the number of applications were summed for each active ingredient in such a product, the total number of applications would be more than one, even though only one application of the product was made.

Errors

In any database with millions of records there will almost certainly be errors. Most of the values in the PUR are checked for errors and where possible corrections are made. However, some errors will remain. If a value is completely unknown the value will either be left blank for numeric fields or replaced with a "?" or " UNKNOWN" in character fields.

If a reported rate of use (pounds of pesticide per area treated) was so large it was probably in error, the rate was replaced with an estimated rate equal to the median rate of all applications of the pesticide product on the same crop or other site treated. Since the error could have been in the pounds reported or the area or unit treated, the value that was most unusual was the one replaced with an estimate. In some cases, a reasonable estimate could not be made, for example, if there were no or few other reported applications of the product on the site. In these cases, the pounds value was set equal to 0.

Pesticide rates were considered outliers if (1) they were higher than 200 pounds of active ingredient per acre (or greater than 1,000 pounds per acre for fumigants); (2) they were 50 times larger than the median rate for all uses with the same pesticide product, crop treated, unit treated, and record type (that is, production agricultural or all other uses); or (3) they were higher than a value determined by a neural network procedure that approximates what a group of 12 scientists believed were obvious outliers. Although these criteria identified as outliers less than one percent of the rate values in the PUR, some rates were so large that if included in the sums, they would have significantly affected total pounds applied of some pesticides.




III. DATA SUMMARY

This report is a summary of data submitted to DPR. Total pounds may change slightly due to ongoing error correction. The revised numbers, when available, will more accurately reflect the total pounds applied.

Pesticide Use In California

In 2008, there were 161,531,155 pounds of pesticide active ingredients reported used in California. Annual use has varied from year to year since full use reporting was implemented in 1990. For example, reported pesticide use was 172 million pounds in 2007, 190 million pounds in 2006, and 195 million pounds in 2005.

Such variances are, and will continue to be, a normal occurrence. These fluctuations can be attributed to a variety of factors, including changes in planted acreage, crop plantings, pest pressures, and weather conditions. For example, extremely heavy rains result in excessive weeds, thus more pesticides may be used; drought conditions may result in fewer planted acres, thus less pesticide may be used.

As in previous years, the greatest pesticide use occurred in California’s San Joaquin Valley (Table 1). Four counties in this region had the highest use:  Fresno, Kern, Tulare, and San Joaquin.

Table 2 breaks down the pounds of pesticide use by general use categories:  production agriculture, post-harvest commodity fumigation, structural pest control, landscape maintenance, and all others.

Pesticide Sales In California

Reported pesticide applications are only a portion of the pesticides sold each year. Typically, about two-thirds of the pesticide active ingredients sold in a given year are not subject to use reporting. Examples of non-reported active ingredients are chlorine (used primarily for municipal water treatment) and home-use pesticide products.

Sales data for 2008 are not yet available as they are in the process of being reviewed and will be released in January 2010. There were 679 million pounds sold in 2007, 743 million pounds sold in 2006, and 611 million pounds in 2005. Prior years data are posted on DPR’s web site; click "A - Z Index", "Sales of pesticides".

In addition, it should be noted that the pounds of pesticides used and the number of applications are not necessarily accurate indicators of the extent of pesticide use or, conversely, the extent of use of reduced-risk pest management methods. For example, farmers may make a number of small-scale " spot" applications targeted at problem areas rather than one treatment of a large area. They may replace a more toxic pesticide used at one pound per acre with a less hazardous compound that must be applied at several pounds per acre. Either of these scenarios could increase the number of applications or amount of pounds used, respectively, without indicating an increased reliance on pesticides.

Table 1. Total pounds of pesticide active ingredients reported in each county and rank during 2007 and 2008.

  2007 Pesticide Use 2008 Pesticide Use
County Pounds Applied Rank Pounds Applied Rank
Alameda 278,934 41 320,559 38
Alpine 1,033 58 472 57
Amador 99,692 44 82,304 45
Butte 3,083,724 14 2,481,130 16
Calaveras 45,509 48 33,458 50
Colusa 2,062,102 21 2,067,987 21
Contra Costa 632,000 34 456,573 35
Del Norte 333,059 38 321,641 37
El Dorado 193,053 42 99,682 44
Fresno 26,013,286 1 27,543,587 1
Glenn 2,301,269 20 1,085,894 25
Humboldt 57,950 46 61,943 47
Imperial 5,049,024 11 3,740,014 12
Inyo 2,328 56 5,871 54
Kern 25,984,379 2 25,441,400 2
Kings 5,651,973 10 6,239,993 9
Lake 571,885 35 601,928 34
Lassen 40,027 49 125,312 43
Los Angeles 2,517,364 18 2,741,761 14
Madera 8,965,193 5 7,578,258 5
Marin 46,887 47 68,953 46
Mariposa 8,985 54 5,795 55
Mendocino 1,946,646 22 952,825 29
Merced 7,068,429 7 6,912,082 6
Modoc 163,780 43 389,141 36
Mono 1,274 57 3,669 56
Monterey 8,543,087 6 7,893,327 4
Napa 1,648,774 25 1,137,388 24
Nevada 92,450 45 35,207 49
Orange 1,129,631 28 1,049,118 27
Placer 295,836 39 240,765 41
Plumas 21,902 51 59,385 48
Riverside 2,638,581 17 2,278,421 20
Sacramento 3,265,539 13 3,411,537 13
San Benito 653,829 33 676,656 33
San Bernardino 373,281 36 273,532 40
San Diego 1,477,784 26 868,254 30
San Francisco 14,935 52 10,514 53
San Joaquin 9,135,807 4 6,754,501 7
San Luis Obispo 1,887,416 23 2,400,818 18
San Mateo 290,190 40 306,063 39
Santa Barbara 4,485,300 12 4,279,799 11
Santa Clara 931,918 31 1,173,078 23
Santa Cruz 1,843,778 24 1,653,785 22
Shasta 336,292 37 206,984 42
Sierra 8,338 55 156 58
Siskiyou 1,317,335 27 1,074,184 26
Solano 813,654 32 818,358 31
Sonoma 2,702,102 16 2,402,744 17
Stanislaus 5,818,539 9 5,677,506 10
Sutter 2,813,006 15 2,613,894 15
Tehama 1,088,398 30 997,693 28
Trinity 9,929 53 13,186 52
Tulare 15,317,559 3 14,310,365 3
Tuolumne 27,890 50 19,407 51
Ventura 6,214,628 8 6,437,899 8
Yolo 2,459,795 19 2,295,955 19
Yuba 1,102,630 29 798,445 32
Total 171,879,918   161,531,155  

 

Table 2. Pounds of pesticide active ingredients, 1997 - 2008, by general use categories.

Year Production
Agriculture
Postharvest
Fumigation
Structural
Pest Control
Landscape
Maintenance
All Others* Total Pounds
1997 192,619,440 1,720,696 5,185,923 1,225,377 6,972,903 207,724,339
1998 200,945,106 1,707,519 5,930,252 1,396,263 6,832,159 216,811,299
1999 186,572,405 2,021,914 5,673,319 1,398,408 7,871,938 203,537,985
2000 173,304,700 2,127,380 5,186,685 1,403,069 6,780,506 188,802,340
2001 139,371,107 1,436,475 4,921,897 1,282,302 6,264,514 153,276,293
2002 154,703,941 1,804,328 5,468,290 1,440,444 6,688,403 170,105,407
2003 160,103,275 1,780,497 5,174,892 1,961,076 7,401,377 176,421,117
2004 164,893,797 1,860,020 5,118,025 1,600,307 6,972,790 180,444,940
2005 177,096,305 2,256,918 5,623,223 1,761,327 8,490,962 195,228,734
2006 167,791,431 2,106,010 5,272,051 2,269,888 10,310,038 187,749,419
2007 156,688,188 2,278,310 3,966,061 1,654,737 7,292,622 171,879,918
2008 147,085,280 2,538,800 3,223,172 1,581,956 7,101,995 161,531,202

* This category includes pesticide applications reported in the following general categories:  pest control on rights-of-way; public health which includes mosquito abatement work; vertebrate pest control; fumigation of nonfood and nonfeed materials such as lumber, furniture, etc.; pesticide used in research; and regulatory pest control used in ongoing control and/eradication of pest infestations.

 

IV. TRENDS IN USE IN CERTAIN PESTICIDE CATEGORIES

Reported pesticide use in California in 2008 totaled 162 million pounds, a decrease of nearly 10 million pounds from 2007. Production agriculture, the major category of use subject to reporting requirements, accounted for most of the overall decrease in use. Applications decreased by 9.6 million pounds for production agriculture. Similarly, there was a 740,000 pound decrease in structural pest control, a decrease of 73,000 pounds in landscape maintenance, and a 190,000 pound decrease of other reported non-agricultural use. However, there was an increase of 260,000 pounds in post-harvest treatments.

The active ingredients (AI) with the largest uses by pounds in 2008 were sulfur, petroleum and mineral oils, 1,3-dichloropropene (1,3-D), metam -sodium, and glyphosate. Sulfur was the most highly used non-adjuvant pesticide in 2008, both in pounds applied and acres treated. By pounds, sulfur accounted for 25 percent of all reported pesticide use. Sulfur is a natural fungicide favored by both conventional and organic farmers.

Most of the decline in all reported pesticide use was from sulfur, which decreased by 5.7 million pounds (12 percent). Other non-adjuvant pesticides that declined in use include copper fungicides (1.2 million pound decrease, 17 percent), methyl bromide (790,000 pound decrease, 12 percent), metam-sodium (680,000 pound decrease, 7 percent), octhilinone (410,000 pound decrease, 92 percent), and glyphosate (320,000 pound decrease, 4 percent).

In contrast, some pesticide use increased. Non-adjuvant pesticides with the greatest increase in pounds applied were potassium n- methyldithiocarbamate (also called metam-potassium) (1.7 million pound increase, 45 percent), calcium hydroxide (520,000 pound increase, 12 percent), chlorine (420,000 pound increase, 49 percent), and pendimethalin (320,000 pound increase, 29 percent).

Major crops or sites that showed an overall increase in pesticide pounds applied from 2007 to 2008 include carrot (1.0 million pounds increase), processing tomato (910,000 pounds increase), preplant soil fumigation (540,000 pounds), fresh market tomato (450,000 pounds), and public health (270,000 pounds). Major crops or sites with decreased pounds applied include wine grape (3.0 million pounds decrease), table and raisin grape, (2.8 million pounds), cotton (1.0 million pounds), lumber (1.0 million pounds), and orange (821,000 pounds. For the crops in this list the change in pounds applied was often different than the change in acres planted . Acreage of most crops decreased, though a few increased slightly (Table 3).

DPR data analyses have shown that pesticide use varies from year to year depending upon pest problems, weather, acreage and types of crops planted, economics, and other factors. Of the different AI types, fungicides had the greatest decrease by both pounds and acres treated. Herbicide use also decreased by pounds and acres treated. Insecticide use declined by pounds applied but acres treated increased marginally. Conversely, pounds of fumigants increased slightly but acres treated decreased slightly.

Pesticide use is reported as the number of pounds of AI and the total number of acres treated. The data for pounds include both agricultural and nonagricultural applications; the data for acres treated are primarily agricultural applications. The number of acres treated means the cumulative number of acres treated; the acres treated in each application are summed even when the same field is sprayed more than once in a year. (For example, if one acre is treated three times in a season with an individual AI, it is counted as three acres treated in the tables and graphs in Sections IV and V of this report.)

Table 3. The change in pounds of AI applied and acres planted or harvested and the percent change from 2007 and 2008 for the crops or sites with the greatest change in pounds applied.

  Change Percent Change
Crop or Site Treated Lbs 08-07 Acres 08-07 Lbs 08-07 Acres 08-07
CARROT 1,048,038 -8,400 13 -11
TOMATO, PROCESSING 909,714 -20,000 9 -7
SOIL FUMIGATION/PREPLANT 535,098   16  
TOMATO, FRESH MARKET 445,502 0 32 0
PUBLIC HEALTH 273,448   18  
ORANGE -823,708 1,000 -8 1
LUMBER, TREATED -1,044,112   -83  
COTTON -1,045,578 -180,000 -30 -40
GRAPE, TABLE AND RAISIN -2,755,613 -7,000 -16 -2
GRAPE, WINE -2,987,853 3,000 -12 1

To provide an overview, pesticide use is summarized for eight different pesticide categories from 1998 to 2008 (Tables 4–11) and from 1994 to 2008 (Figures 1–8). These categories classify pesticides according to certain characteristics such as reproductive toxins, carcinogens, or reduced-risk characteristics. Use of most pesticide categories decreased from 2007 to 2008, except for increases in pounds of fumigants and acres treated with oils. Some of the major changes from 2007 to 2008 include:

  • Chemicals classified as reproductive toxins decreased in pounds applied from 2007 to 2008 (down 1.7 million pounds or 10 percent) and decreased in acres treated (down 182,000 acres or 10 percent). The decrease in pounds was mostly from the reduced use of the fumigants methyl bromide and metam-sodium and the decrease in acres was mostly from decreases in the use of the miticide propargite and the fungicide myclobutanil. Pesticides in this category are those listed on the State’s Proposition 65 list of chemicals "known to cause reproductive toxicity."
  • Use of chemicals classified as carcinogens decreased from 2007 to 2008 (down 1.7 million pounds or 7 percent and down 600,000 acres or 17 percent). The decrease in pounds was mainly due to a decrease in use of the fumigant metam-sodium and the fungicides maneb and chlorothalonil. The decrease in acres treated was mostly from decreases in the use of the herbicide diuron and fungicides maneb and chlorothalonil. The pesticides in this category are those listed by U.S. EPA as B2 carcinogens or on the State’s Proposition 65 list of chemicals "known to cause cancer".
  • Use of cholinesterase-inhibiting pesticides (organophosphate (OP) and carbamate pesticides), which include compounds of high regulatory concern, continued to decline as they have for nearly every year since 1995. Use decreased from 2007 to 2008 both in pounds (down 720,000 or 12 percent) and in acres treated (down 590,000 acres or 12 percent). The AIs with the greatest decreases in pounds were ethephon, diazinon, phosmet, and chlorpyrifos; the AIs with the greatest decreases in acres treated were ethephon, diazinon, and methomyl. Although use of most OPs and carbamates decreased; the use of oxamyl (insecticide), naled (insecticide), and malathion (insecticide) increased.
  • Use of most chemicals categorized as ground water contaminants decreased by pounds (down 270,000 pounds or 17 percent), and by acres treated (down 300,000 acres or 25 percent) in 2008 compared to 2007. The decreases in pounds and acres treated were mostly from decreases in use of the herbicides diuron and simazine.
  • Chemicals categorized as toxic air contaminants, another group of pesticides of regulatory concern, decreased from 2007 to 2008 both in pounds (down 50,000 pounds or 0.13 percent) and by acres treated (down 370,000 acres or 12 percent). When summarized by pounds, most toxic air contaminants are fumigants, which are used at high rates. When summarized by acres treated, the main toxic air contaminants were the herbicides trifluralin and 2,4-D, dimethylamine salt and the fungicide maneb.
  • The pounds of fumigant chemicals applied increased marginally in 2008 from 2007 (up 228,000 pounds or 0.6 percent) but decreased in cumulative acres treated (down 3,100 acres or 0.9 percent). Pounds of four of the six major fumigants decreased (metam-sodium, sulfuryl fluoride, methyl bromide, and 1,3-D) and pounds of two fumigants increased (potassium n-methyldithiocarbamate, and chloropicrin).
  • Pounds of oil pesticides decreased (down 214,000 pounds or less than 1 percent) but increased by acres treated (up 100,000 acres or 3 percent). Oils include many different chemicals, but the category used here includes only ones derived from petroleum distillation. Some of these oils may be on the State ’s Proposition 65 list of chemicals “known to cause cancer” but most serve as alternatives to highly toxic pesticides. Oils are also used by organic growers.
  • Pounds of biopesticides was nearly the same in 2008 as in 2007 but decreased by acres treated (down 160,000 acres or 8 percent) from 2007 to 2008. The most used biopesticide by weight was Bacillus thuringiensis (Bt) (combining all subspecies) and the most used by acres treated were gibberellins, propylene glycol, and Bt. Bt also had the largest increase by pounds. The AIs with the largest decreases in pounds were neem oil, Myrothecium verrucaria, and potassium bicarbonate. The AIs with the greatest decreases in acres treated were propylene glycol, Bt, indole-3-butyric acid (IBA), and 1- naphthalene acetic acid (NAA). AIs with the greatest increase in acres treated were gibberellins and s-methoprene. Biopesticides include microorganisms and naturally occurring compounds, or compounds essentially identical to naturally occurring compounds not toxic to the target pest (such as pheromones).

Since 1993, the reported pounds of pesticides applied have fluctuated from year to year. An increase or decrease in use from one year to the next or in the span of a few years does not necessarily indicate a general trend in use; it simply may reflect variations related to various factors (e.g. climate or economic changes). Short periods of time (three to five years) may suggest trends, such as the increased pesticide use from 2001 to 2005 or the decreased use from 1998 to 2001. However, regression analyses on use from 1993 to 2008 do not indicate a significant trend of either increase or decrease in total pesticide use.

To improve data quality when calculating the total pounds of pesticides, DPR excluded values that were so large they were probably in error. The procedure to exclude probable errors involved the development of complex error-checking algorithms, a data improvement process that is ongoing.

Over-reporting errors have a much greater impact on the numerical accuracy of the database than under-reporting errors. For example, if a field is treated with 100 pounds of a pesticide AI and the application is erroneously recorded as 100,000 pounds (a decimal point shift of three places to the right), an error of 99,900 pounds is introduced into the database. If the same degree of error is made in shifting the decimal point to the left, the application is recorded as 0.1 pound, and an error of 99.9 pounds is entered into the database.

The summaries detailed in the following use categories are not intended to serve as indicators of pesticide risks to the public or the environment. Rather, the data supports DPR regulatory functions to enhance public safety and environmental protection. (See “How Pesticide Data are Used” on page 2.)

 

USE TRENDS OF PESTICIDES ON THE STATE’S PROPOSITION 65 LIST OF CHEMICALS THAT ARE “KNOWN TO CAUSE REPRODUCTIVE TOXICITY”

Table 4A.The reported pounds of pesticides used which are on the State ’s Proposition 65 list of chemicals that are “known to cause reproductive toxicity.” Use includes both agricultural and reportable non- agricultural applications. Data are from the Department of Pesticide Regulation's Pesticide Use Reports

Table 4B. The reported cumulative acres treated with pesticides that are on the State’s Proposition 65 list of chemicals “known to cause reproductive toxicity.” Use includes primarily agricultural applications. The grand total for acres treated may be less than the sum of acres treated for all active ingredients because some products contain more than one active ingredient. Data are from the Department of Pesticide Regulation's Pesticide Use Reports.

Figure 1. Use trends of pesticides that are on the State ’s Proposition 65 list of chemicals that are “known to cause reproductive toxicity.” Reported pounds of active ingredient (AI) applied include both agricultural and non-agricultural applications. The reported cumulative acres treated include primarily agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

 

USE TRENDS OF PESTICIDES LISTED BY U.S. EPA AS CARCINOGENS OR BY THE STATE AS “KNOWN TO CAUSE CANCER”

Table 5A. The reported pounds of pesticides used that are listed by U.S. EPA as B2 carcinogens or that are on the State’s Proposition 65 list of chemicals “known to cause cancer.” Use includes both agricultural and reportable non-agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

Table 5B. The reported cumulative acres treated with pesticides listed by U.S. EPA as B2 carcinogens or on the State’s Proposition 65 list of chemicals “ known to cause cancer.” Use includes primarily agricultural applications. The grand total for acres treated is less than the sum of acres treated for all active ingredients because some products contain more than one active ingredient. Data are from the Department of Pesticide Regulation’s Pesticide Use.

Figure 2. Use trends of pesticides that are listed by U.S. EPA as B2 carcinogens or that are on the State’s Proposition 65 list of chemicals “known to cause cancer.” Reported pounds of active ingredient (AI) applied include both agricultural and reportable non-agricultural applications. The reported cumulative acres treated include primarily agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

 

USE TRENDS OF CHOLINESTERASE-INHIBITING PESTICIDES

Table 6A. The reported pounds of cholinesterase-inhibiting pesticides used. These pesticides are organophosphate and carbamate active ingredients. Use includes both agricultural and reportable non-agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports

Table 6B. The reported cumulative acres treated with cholinesterase- inhibiting pesticides. These pesticides are organophosphate and carbamate active ingredients. Use includes primarily agricultural applications. The grand total for acres treated is less than the sum of acres treated for all active ingredients because some products contain more than one active ingredient. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

Figure 3. Use trends of cholinesterase-inhibiting pesticides, which includes pesticides with organophosphate and carbamate active ingredients. Reported pounds of active ingredient (AI) applied include both agricultural and reportable non-agricultural applications. The reported cumulative acres treated include primarily agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

 

USE TRENDS OF PESTICIDES ON DPR’S GROUND WATER PROTECTION LIST

Table 7A. The reported pounds of pesticides on the "a" part of DPR’s groundwater protection list. These pesticides are the active ingredients listed in the California Code of Regulations, Title 3, Division 6, Chapter 4, Subchapter 1, Article 1, Section 6800(a). Use includes both agricultural and reportable non-agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

Table 7B. The reported cumulative acres treated with pesticides on the "a" part of DPR’s groundwater protection list. These pesticides are the active ingredients listed in the California Code of Regulations, Title 3, Division 6, Chapter 4, Subchapter 1, Article 1, Section 6800(a). Use includes both agricultural and reportable non-agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

Figure 4.Use trends of pesticides on DPR’s groundwater protection list. These pesticides are the active ingredients listed in the California Code of Regulations, Title 3, Division 6, Chapter 4, Subchapter 1, Article 1, Section 6800(a). Reported pounds of active ingredient (AI) applied include both agricultural and reportable non-agricultural applications. The reported cumulative acres treated include primarily agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

 

USE TRENDS OF PESTICIDES ON DPR’S TOXIC AIR CONTAMINATS LIST

Table 8A. The reported pounds of pesticides on DPR’s toxic air contaminants list applied in California. These pesticides are the active ingredients listed in the California Code of Regulations, Title 3, Division 6, Chapter 4, Subchapter 1, Article 1, Section 6860. Use includes both agricultural and reportable non-agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

Table 8B. The reported cumulative acres treated in California with pesticides on DPR’s toxic air contaminants list. These pesticides are the active ingredients listed in the California Code of Regulations, Title 3, Division 6, Chapter 4, Subchapter 1, Article 1, Section 6860. Use includes primarily agricultural applications. The grand total for acres treated is less than the sum of acres treated for all active ingredients because some products contain more than one active ingredient. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

Figure 5. Use trends of pesticides on DPR’s toxic air contaminants list. These pesticides are the active ingredients listed in the California Code of Regulations, Title 3, Division 6, Chapter 4, Subchapter 1, Article 1, Section 6860. Reported pounds of active ingredient (AI) applied include both agricultural and reportable non-agricultural applications. The reported cumulative acres treated include primarily agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

 

USE TRENDS OF FUMIGANT PESTICIDES

Table 9A. The reported pounds of fumigant pesticides used. Use includes both agricultural and reportable non-agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

Table 9B. The reported cumulative acres treated with fumigant pesticides. Use includes both agricultural and reportable non-agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

Figure 6. Use trends of fumigant pesticides. Reported pounds of active ingredient (AI) applied include both agricultural and reportable non-agricultural applications. The reported cumulative acres treated include primarily agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

 

USE TRENDS OF OIL PESTICIDES 

Table 10A. The reported pounds of oil pesticides. As a broad group, oil pesticides and other petroleum distillates are on U.S. EPA’s list of B2 carcinogens or the State’s Proposition 65 list of chemicals “known to cause cancer.” However, these classifications do not distinguish among oil pesticides that may not qualify as carcinogenic due to their degree of refinement. Many such oil pesticides also serve as alternatives to high-toxicity chemicals. For this reason, oil pesticide data was classified separately in this report. Use includes both agricultural and reportable non-agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

Table 10B. The reported cumulative acres treated in California with oil pesticides. (See qualifying comments on U.S. EPA B2 carcinogen and Proposition 65 listing with Table 9A.) Uses include primarily agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

Figure 7. Use trends of oil pesticides. As a broad group, oil pesticides and other petroleum distillates are on U.S. EPA’s list of B2 carcinogens or the State’s Proposition 65 list of chemicals “known to cause cancer.” However, these classifications do not distinguish among oil pesticides that may not qualify as carcinogenic due to their degree of refinement. Many such oil pesticides also serve as alternatives to high-toxicity chemicals. For this reason, oil pesticide data was classified separately in this report. Reported pounds of active ingredient (AI) applied include both agricultural and reportable non-agricultural applications. The reported cumulative acres treated include primarily agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

 

USE TRENDS OF BIOPESTICIDES

Table 11A. The reported pounds of biopesticides applied in California. Biopesticides include microorganisms and naturally occurring compounds, or compounds essentially identical to naturally occurring compounds that are not toxic to the target pest (such as pheromones). Use includes both agricultural and non-agricultural applications. Zero values in early years likely indicate the pesticide was not yet registered for use. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

Table 11B. The reported cumulative acres treated in California with each biopesticide. Biopesticides includes microorganisms and naturally occurring compounds, or compounds essentially identical to naturally occurring compounds that are not toxic to the target pest (such as pheromones). Use includes primarily agricultural applications. The grand total for acres treated is less than the sum of acres for all active ingredients because some products contain more than one active ingredient. Zero values in early years likely indicate the pesticide was not yet registered for use. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.

Figure 8. Use trends of biopesticides. Biopesticides include microorganisms and naturally occurring compounds, or compounds essentially identical to naturally occurring compounds that are not toxic to the target pest (such as pheromones). Reported pounds of active ingredient (AI) applied include both agricultural and reportable non-agricultural applications. The reported cumulative acres treated include primarily agricultural applications. Data are from the Department of Pesticide Regulation’s Pesticide Use Reports.




V. TRENDS IN PESTICIDE USE IN CERTAIN COMMODITIES

This summary describes possible reasons for changes in pesticide use from 2007 to 2008 for the following commodities: (1)  almonds, (2)  wine grapes, (3)  table and raisin grapes, (4)  alfalfa, (5) cotton, (6)  processing tomatoes, (7) oranges, (8) rice, (9) head lettuce, (10)  walnuts, (11) peaches and nectarines, (12) strawberries, and (13) carrots. These 13 commodities were chosen because each was treated with more than 3 million pounds of active ingredients (AIs) or cumulatively treated on more than 1.9 million acres. Collectively, this represents 70 percent of all reported pesticide pounds used (76 percent of all pounds used on agricultural fields) and 72 percent of the acres treated in 2008.

Information used to develop this section was drawn from several publications and phone interviews with pest control advisors, growers, University of California Cooperative Extension farm advisors and specialists, researchers, and commodity association representatives. DPR staff analyzed the information, using their knowledge of pesticides, California agriculture, pests, and pest management practices to draw conclusions about possible explanations for changes in pesticide use. However, it is important to note these explanations are based on anecdotal information, not rigorous statistical analyses.

Reported pesticide use in California in 2008 totaled 162 million pounds, a decrease of 10 million pounds from 2007 (6.0 percent). The AIs with the largest uses by pounds were sulfur, petroleum and mineral oils, 1,3-dichloropropene (1,3-D), metam-sodium, and glyphosate. Sulfur accounted for 25 percent of all reported pesticide use in 2008. Sulfur use decreased by 5.7 million pounds (12 percent) from 2007 to 2008, and accounted for most of the decrease in pounds of AI. Sulfur is a natural fungicide favored by both conventional and organic farmers and is used mostly to control powdery mildew on grapes and processing tomatoes. Other pesticides that declined in use include copper-based pesticides (1.2 million pound decrease, 17 percent), the fumigant methyl bromide (790,000 pound decrease, 12 percent), the fumigant metam-sodium (680,000 pound decrease, 7 percent), and the wood preservative octhilinone (410,000 pound decrease, 92 percent). Oils are used mostly as insecticides and miticides in orchards. Copper-based pesticides are used mostly in rice, oranges, walnuts, almonds, and grapes; methyl bromide is used mostly for strawberries and nurseries; metam-sodium is used for carrots, potatoes, and processing tomatoes; and glyphosate, an herbicide, is used mostly on almonds, rights of way, wine grapes, and landscaping.

In contrast, use of some pesticides increased. Pesticides with the greatest increase in pounds applied were the fumigant potassium n-methyldithiocarbamate (also called metam-potassium) (1.7 million pound increase, 45 percent), the adjuvant calcium hydroxide (520,000 pound increase, 12 percent), the disinfectant chlorine (420,000 pounds increase, 49 percent), and the herbicide pendimethalin (320,000 pounds increase, 29 percent). Metam-potassium was used mostly for tomatoes and carrots and its use increased primarily as a replacement for other fumigants. The use of all fumigants was nearly the same in 2008 as in 2007. Pendimethalin was used mostly in alfalfa and almonds but the increase in use was in alfalfa.

Different pesticides are used at different rates. In California, most pesticides are applied at rates of around 1 to 2 pounds per acre. However, fumigants are usually applied at rates of hundreds of pounds per acre. Thus, comparing use by pounds will emphasize fumigants. Comparing use among different pesticides using acres treated gives a different picture.

Total acres treated with all pesticides in 2008 was 66 million, a decrease from 2007 of 2 million (3.3 percent). By acres treated, the non-adjuvant pesticides with the greatest use in 2008 were sulfur, glyphosate, oils, oxyfluorfen, and copper compounds. Most of the decrease in total acres treated was from decreases in sulfur and spinosad, with smaller decreases in paraquat dichloride, glyphosate, and trifluralin. AIs with the largest increase in acres treated were spinetoram and glufosinate-ammonium; smaller increases occurred with lambda-cyhalothrin, pendimethalin, and indoxacarb. Glyphosate, oxyfluorfen, paraquat dichloride, and trifluralin are all herbicides, mostly used on almonds, grapes, and alfalfa. Spinosad is an insecticide use mostly on lettuce, oranges, olives, and grapes. Spinetoram is a new insecticide, first used in California in 2007, mostly on lettuce and strawberries. Glufosinate-ammonium is an herbicide used mostly in almonds and grapes.

DPR data analyses have shown that pesticide use varies from year to year depending upon pest problems, weather, acreage and types of crops planted, economics, and other factors. The winter and spring of 2008 were relatively dry which probably resulted in less weed and disease pressure. Lygus bugs were a problem in some areas for cotton and strawberries because of changing cropping patterns. Also, mites were a problem for some crops because of the dry, hot summer. The reduction in spinosad use was due to increased use of spinetoram, a second-generation version of spinosad. Use of glufosinate-ammonium, a fairly recent herbicide, has probably increased as a replacement for some use of glyphosate, because of increased prevalence of glyphosate-resistant weeds.

In the following tables, use is given by pounds of AI applied and by acres treated. Acres treated means the cumulative number of acres treated; the acres treated in each application are summed even when the same field is sprayed more than once in a year. (For example, if the same acre is treated three times in a calendar year with an individual AI, it is counted as three acres treated).

Almonds

There are three distinct almond growing regions in California: the Sacramento Valley, Central San Joaquin Valley and Southern San Joaquin Valley. Weather conditions and pest pressure vary greatly from the northern region to the south. Almonds are California’s largest tree nut crop in total dollar value and acreage and are the largest horticultural export from the United States. Total worldwide shipments increased 18 percent in fiscal year 2007/2008 reaching a total of 1.26 billion pounds.

Table 12A. Total reported pounds of all active ingredients (AI), acres treated, acres planted, and prices for almonds each year from 2004 to 2008. Planted acres from 2003 to 2007 are from CDFA, 2008; planted acres in 2008 are from NASS, May 2009; and marketing year average prices from 2003 to 2008 are from NASS, August 2009. Acres treated means cumulative acres treated (see explanation p. 11).

 
2004
2005
2006
2007
2008
Lbs AI
16,189,822
17,133,637
21,249,205
19,538,857
19,174,395
Acres Treated
7,316,210
8,898,957
11,226,899
10,464,255
10,035,599
Acres Planted
640,000
690,000
730,000
740,000
795,000
Price $/lbs
$2.21
$2.81
$2.06
$1.75
$1.40

Table 12B. Percent difference from previous year for reported pounds of all AIs, acres treated, acres planted and prices for almonds each year from 2004 to 2008.

 
2004
2005
2006
2007
2008
Lbs AI
21
6
24
-8
-2
Acres Treated
15
22
26
-7
-4
Acres Planted
5
8
6
1
7
Price $/lbs
41
27
-27
-15
-20

Figure 9. Acres of almonds treated by all AIs in the major types of pesticides from 1994 to 2008.

Figure 9

Table 12C. The non-adjuvant pesticides with the largest change in acres treated of almonds from 2007 to 2008. This table shows acres treated with each AI in each year from 2004 to 2008, the change in acres treated and percent change from 2007 to 2008.

AI
AI TYPE
2004
2005
2006
2007
2008
Change
Pct Change
OIL
 INSECTICIDE
483,367
544,607
680,308
730,564
822,304
91,741
13
PARAQUAT DICHLORIDE
 HERBICIDE
242,179
286,201
349,596
335,509
256,183
-79,326
-24
GLYPHOSATE
 HERBICIDE
1,034,569
1,223,314
1,343,037
1,316,550
1,242,707
-73,843
-6
GLUFOSINATE-AMMONIUM
 HERBICIDE
7,986
30,358
62,777
129,008
201,060
72,052
56
CHLORPYRIFOS
 INSECTICIDE
153,321
155,355
293,689
227,409
157,563
-69,846
-31
PYRIPROXYFEN
 INSECTICIDE
76,974
91,566
101,867
1.00E+05
161,339
61,414
61
PROPICONAZOLE
 FUNGICIDE
87
245
216
128
56,039
55,911
43,681
FLUMIOXAZIN
 HERBICIDE
 
72,753
119,285
157,526
107,544
-49,981
-32
AZOXYSTROBIN
 FUNGICIDE
100,953
255,380
219,046
79,259
39,527
-39,732
-50
CYPRODINIL
 FUNGICIDE
266,986
268,997
234,041
151,630
114,081
-37,549
-25
ZIRAM
 FUNGICIDE
61,926
104,207
155,830
90,259
53,534
-36,725
-41
MYCLOBUTANIL
 FUNGICIDE
50,734
48,825
29,967
51,188
15,991
-35,196
-69
BOSCALID
 FUNGICIDE
74,064
266,613
473,272
271,143
236,133
-35,010
-13
PYRACLOSTROBIN
 FUNGICIDE
74,064
266,613
473,272
271,130
236,133
-34,997
-13
RIMSULFURON
 HERBICIDE
 
 
 
2,554
35,188
32,635
1,278

Total pesticides applied in 2008, looking at acres treated and pounds AI applied were slightly lower compared to 2007. Weather in 2008 could be described as a ‘mixed bag.’ Conditions were characterized by alternating periods of wet and dry, temperature swings from cool to hot including periods where hot dry winds increased moisture loss. Smoky conditions caused by numerous fires up and down the state were thought by some to have affected crop maturity. Dry conditions overall resulted in a reduction in the use of most fungicides. Exceptions were increased use of pyrimethanil, propiconazole, difenoconozole and fenbuconozole. Use of pyrimethanil increased to help manage strobilurin-resistant alternaria and almond scab. Propiconozole, difenconozole and fenbuconozole are new materials that also fit well into a resistance management program.

Key arthropod pests in almonds are navel orangeworm (NOW), San Jose scale (SJS), peach twig borer (PTB), web-spinning mites, and ants. Data from 2008 show growers are shifting from broad-spectrum to reduced-risk insecticides. Winter sanitation to eliminate mummy nuts has become a standard practice to reduce over wintering NOW larva. Acres treated with oils alone in the dormant season increased 11 percent in 2008. Dormant sprays with oils alone were applied to control low to moderate populations of SJS. Other insecticides were added with the oil to control high populations of SJS and PTB. Compliance with European Union (EU) aflatoxin levels is an industry concern. Since insect damage to almond nuts can contribute to invasion by molds that produce aflatoxin, some growers changed their insecticide program specifically to protect the crop from insect damage that could compromise EU shipments.

In general, worms were not a big problem in 2008. In-season use of insecticides for worm control was slightly higher in 2008 compared to 2007. Notable increases in acres treated included methoxyfenozide, esfenvalerate, diflubenzuron, and bifenthrin. Acres treated with bifenthrin (Brigade) were up in 2008 to control navel orangeworm. Brigade is a new pyrethroid product that has been shown to be effective against NOW, and does not flare mites like esfenvalerate and some of the older pyrethroids do. One Brigade treatment for NOW and a reduced-risk methoxyfenozide spray to control PTB, when necessary, are reportedly replacing conventional azinphos-methyl and phosmet treatments at hull split. Use of spinetoram, a new product that is effective in controlling NOW, showed a big increase in acres treated in 2008. Correspondingly, use of chlorpyrifos, permethrin, and phosmet were down, chlorpyrifos by as much as 30 percent.

Mites were a problem later in the 2008 season due to dry, hot weather. Acres treated with abamectin increased compared to 2007. Other increases included use of hexythiazox, etoxizole, fenproximate, bifenazate, spirodiclofen, and s-methoprene. As a result acres treated with propargite were down over 30 percent.

Growers reported treatment for ants in all growing regions using abamectin or pyriproxifen (Esteem). The use of abamectin for both mites and ants may have been a factor in the increased use.

The number of acres treated with herbicides in 2008 decreased slightly but overall was pretty close to that treated in 2007. The increased use of glufosinate-ammonium and rimsulferon, used to control glyphosate-resistant weeds, were notable exceptions.

Total pounds applied and acres treated with 1,3-dichloropropene, methyl bromide, and sodium tetrathiocarbonate decreased in 2008 and use of chloropicrin increased. Chloropicrin was reportedly the material of choice in 2008 to control replant disease.

Wine grapes

In 2008, roughly 62 percent of California vineyards produced wine grapes. There are four major wine grape production regions: 1) North Coast (Lake, Mendocino, Napa, Sonoma, and Solano counties); 2) Central Coast (Alameda, Monterey, San Luis Obispo, Santa Barbara, San Benito, Santa Cruz, and Santa Clara counties); 3) Northern San Joaquin Valley (San Joaquin, Calaveras, Amador, Sacramento, Merced, Stanislaus, and Yolo counties); and 4) Southern San Joaquin Valley (Fresno, Kings, Tulare, Kern, and Madera counties). The total pounds of pesticide active ingredients applied to wine grapes decreased by 13 percent in 2008 compared to 2007 and acres treated decreased by 9 percent. Factors that influence changes in pesticide use on wine grapes include weather, topography, pest pressures (which vary by region), competition from newer pesticide products, application restrictions, efforts by growers to reduce costs, and increasing emphasis on sustainable farming. The pooled figures in this report may not reflect differences in pesticide use patterns between production regions.

Table 13A. Total reported pounds of all active ingredients (AI), acres treated, acres planted, and prices for wine grapes each year from 2004 to 2008. Planted acres from 2003 to 2007 are from CDFA, 2008; planted acres in 2008 are from NASS, March 2009; and marketing year average prices from 2003 to 2008 are from NASS, August 2009. Acres treated means cumulative acres treated (see explanation p. 11).

 
2004
2005
2006
2007
2008
Lbs AI
27,644,413
33,749,192
23,993,654
24,331,410
21,193,224
Acres Treated
7,272,067
8,723,471
7,842,768
7,866,689
7,169,542
Acres Planted
513,000
522,000
527,000
523,000
526,000
Price $/ton
$570.00
$582.00
$582.00
$564.00
$609.00

Table 13B. Percent difference from previous year for reported pounds of all AIs, acres treated, acres planted and prices for wine grapes each year from 2004 to 2008.

2004
2005
2006
2007
2008
Lbs AI
-3
22
-29
1
-13
Acres Treated
-3
20
-10
0
-9
Acres Planted
-3
2
1
-1
1
Price $/ton
8
2
0
-3
8

Figure 10. Acres of wine grapes treated by all AIs in the major types of pesticides from 1994 to 2008.

Figure 10

Table 13C. The non-adjuvant pesticides with the largest change in acres treated of wine grapes from 2007 to 2008. This table shows acres treated with each AI in each year from 2004 to 2008, the change in acres treated and percent change from 2007 to 2008.

AI
AI TYPE
2004
2005
2006
2007
2008
Change
Pct Change
SULFUR
FUNGICIDE/ INSECTICIDE
2,721,270
3,178,353
2,320,783
2,388,294
1,972,855
-415,439
-17
OIL
INSECTICIDE
89,318
134,231
232,686
292,795
380,824
88,029
30
GLUFOSINATE-AMMONIUM
HERBICIDE
18,891
19,883
90,345
92,699
180,094
87,395
94
GLYPHOSATE
HERBICIDE
464,787
475,458
473,164
471,086
410,108
-60,978
-13
PARAQUAT DICHLORIDE
HERBICIDE
155,644
146,912
177,339
128,737
78,714
-50,023
-39
MYCLOBUTANIL
FUNGICIDE
281,995
293,425
269,688
224,548
180,712
-43,836
-20
FLUMIOXAZIN
HERBICIDE
 
35,746
86,011
111,439
70,782
-40,657
-36
KRESOXIM-METHYL
FUNGICIDE
48,772
67,542
50,470
66,846
39,315
-27,532
-41
SIMAZINE
HERBICIDE
145,260
118,378
143,447
96,437
69,102
-27,335
-28
TEBUCONAZOLE
FUNGICIDE
130,382
177,130
103,719
137,225
116,670
-20,554
-15
BACILLUS PUMILUS, STRAIN QST 2808
FUNGICIDE
4
10,074
16,608
22,284
36,723
14,439
65
RIMSULFURON
HERBICIDE
 
 
 
147
14,258
14,111
9,590
FENHEXAMID
FUNGICIDE
30,663
48,182
33,957
33,173
19,162
-14,010
-42
FENPYROXIMATE
INSECTICIDE
3,982
25,342
23,433
19,509
33,473
13,963
72
THIOPHANATE-METHYL
FUNGICIDE
3,687
7,402
3,930
17,538
3,903
-13,635
-78

The acres treated with insecticides decreased marginally (by 1 percent) from 2007. The major insecticides applied in 2008 by acres treated were imidacloprid, oils, methoxyfenozide, chlorpyrifos, bifenazate, abamectin, etoxazole, and fenpyroximate. Chlorpyrifos is used before budbreak and after harvest to control mealybug infestations; imidacloprid is used during warmer weather between budbreak and harvest. Methoxyfenozide is used to control various moths, such as omnivorous leafroller (Platynota stultana). In 2008, acreage treated with oils increased by 30 percent. Oils have many attractive, broad-spectrum properties and are low-risk. Increasingly mixed with fungicides, oils can replace a surfactant and eradicate mildew growth, as well as suppress mites and insects such as grape leafhoppers. Bifenazate, fenpyroximate, and etoxazole are selective alternatives to older, higher-risk miticides, which have longer worker re-entry periods.

Acres treated with sulfur decreased by 17 percent, while acres treated with all other fungicides decreased by 8.1 percent. Sulfur, copper-based pesticides, pyraclostrobin, boscalid, myclobutanil, and trifloxystrobin were the most-used fungicides in terms of acres treated. Acres treated with lime sulfur in early 2008 against overwintering disease inoculum decreased by 36 percent. Dormant season disease pressure was low in 2008 due to low rainfall. Copper-based pesticides, used to treat downy mildew and botrytis bunch rot, was applied to 3 percent fewer acres in 2008 compared to 2007.

The acres treated with herbicides decreased by 7 percent in 2008 compared to 2007. In terms of acres treated, herbicides used most in wine grapes were glyphosate, oxyfluorfen, glufosinate-ammonium, paraquat, flumioxazin, and simazine. The acres treated with simazine, paraquat, and flumioxazin decreased dramatically, by 28, 39, and 36 percent respectively. In contrast, glufosinate-ammonium-treated acreage doubled from 2007, while rimsulfuron-treated acreage increased 140 times. This is likely due to the increased prevalence of glyphosate-resistant weeds, such as marestail (Conyza canadensis) and fleabane (Conyza bonariensis), in vineyards. Both glufosinate-ammonium and rimsulfuron are used specifically to control these weed species.

Acres treated with Plant growth regulators (PGR) decreased by 18 percent in 2008 compared to 2007. The most common PGRs were gibberellins, which are applied in early spring in order to lengthen and loosen grape clusters. Less compact clusters may be less vulnerable to berry splitting and bunch rot.

Table and Raisin Grapes

Table and raisin grapes comprised approximately 38 percent of California’s total grape crop in 2008, the rest being wine grapes. These categories shift depending on market conditions, since some grape varieties can be used for more than one purpose. Thompson Seedless is the leading raisin grape variety, while Flame Seedless is the leading table grape variety. California produced about 2.2 million tons of raisin grapes and 830,000 tons of table grapes in 2008. Statewide table grape and raisin tonnage increased by 5 percent and 3 percent, respectively, relative to 2007 production.

Table 14A. Total reported pounds of all active ingredients (AI), acres treated, acres planted, and prices for table and raisin grapes each year from 2004 to 2008. Planted acres from 2003 to 2007 are from CDFA, 2008; planted acres in 2008 are from NASS, March 2009; and marketing year average prices from 2003 to 2008 are from NASS, August 2009. Acres treated means cumulative acres treated (see explanation p. 11).

 
2004
2005
2006
2007
2008
Lbs AI
17,557,585
19,395,692
15,245,751
16,368,444
13,746,363
Acres Treated
4,984,244
5,927,808
5,731,725
5,522,212
5,529,126
Acres Planted
340,000
339,000
333,000
325,000
318,000
Price $/ton
$411.26
$310.65
$450.43
$422.09
$308.36

Table 14B. Percent difference from previous year for reported pounds of all AIs, acres treated, acres planted and prices for table and raisin grapes each year from 2004 to 2008.

 
2004
2005
2006
2007
2008
Lbs AI
6
10
-21
7
-16
Acres Treated
-2
19
-3
-4
0
Acres Planted
-4
0
-2
-2
-2
Price $/ton
45
-24
45
-6
-27

Figure 11. Acres of table and raisin grapes treated by all AIs in the major types of pesticides from 1994 to 2008.
Figure 11 

Table 14C. The non-adjuvant pesticides with the largest change in acres treated of table and raisin grapes from 2007 to 2008. This table shows acres treated with each AI in each year from 2004 to 2008, the change in acres treated and percent change from 2007 to 2008.

AI
AI TYPE
2004
2005
2006
2007
2008
Change
Pct Change
SULFUR
 FUNGICIDE/ INSECTICIDE
1,820,909
2,120,638
1,742,570
1,714,758
1,593,236
-121,522
-7
GLUFOSINATE-AMMONIUM
 HERBICIDE
8,644
15,447
46,364
63,141
130,798
67,657
107
GIBBERELLINS
 PLANT GROWTH REGULATOR
311,804
345,991
341,024
339,481
382,892
43,411
13
PARAQUAT DICHLORIDE
 HERBICIDE
106,879
128,530
156,655
119,499
89,866
-29,633
-25
TRIFLOXYSTROBIN
 FUNGICIDE
71,116
117,568
106,542
101,991
128,330
26,339
26
OIL
 INSECTICIDE
31,206
29,819
41,165
69,092
91,046
21,954
32
IMIDACLOPRID
 INSECTICIDE
104,883
63,042
83,349
113,083
93,667
-19,415
-17
BUPROFEZIN
 INSECTICIDE
14,281
22,888
25,899
43,536
62,662
19,126
44
SIMAZINE
 HERBICIDE
98,273
76,110
95,866
75,931
56,876
-19,055
-25
MYCLOBUTANIL
 FUNGICIDE
162,020
169,882
155,368
125,005
141,303
16,298
13
ZIRAM
 FUNGICIDE
4,029
17,146
21,456
26,156
11,327
-14,829
-57
SPINOSAD
 INSECTICIDE
4,670
55,405
52,703
63,840
49,953
-13,887
-22
QUINOXYFEN
 FUNGICIDE
21,091
45,519
38,398
42,572
56,372
13,799
32
DINOTEFURAN
 INSECTICIDE
 
 
3,787
17,459
4,458
-13,001
-74
BIFENAZATE
 INSECTICIDE
34,176
43,682
30,152
29,563
18,154
-11,409
-39

The major insecticides applied in 2008 by acres treated were imidacloprid, oils, cryolite, methoxyfenozide, and buprofezin. The acres treated with insecticides decreased by 11 percent from 2007. Imidacloprid and buprofezin are used during warm weather between budbreak and harvest to control mealybug infestations. Cryolite is a stomach poison applied early in the season to control lepidopterous pests, such as omnivorous leafroller (Platynota stultana). Methoxyfenozide controls similar pests, but can be used later in the growing season than cryolite.

Acres treated with sulfur decreased by 7 percent, while acres treated with all other fungicides also increased by 7 percent. Sulfur, copper-based pesticides, myclobutanil, trifloxystrobin, boscalid, and pryaclostrobin were the most-used fungicides in terms of acres treated. Acres treated with lime sulfur in early 2008 against overwintering disease inoculum decreased by 17 percent. Dormant season disease pressure was low due to low rainfall. Copper-based pesticides, used to treat downy mildew and botrytis bunch rot, was applied to 4 percent fewer acres compared to 2007.

The acres treated with herbicides increased by 5 percent in 2008 compared to 2007. Herbicides used most in table and raisin grapes by acres treated were glyphosate products, glufosinate-ammonium, paraquat, oxyfluorfen, and flumioxazin. The acres treated with paraquat, oxyfluorfen, and glyphosate decreased by 25, 2, and 1 percent respectively. In contrast, glufosinate-ammonium-treated acreage doubled from 2007, while rimsulfuron saw its first year of use in the commodity. Increased use of the two new products is likely due to the increased prevalence of glyphosate-resistant weeds, such as marestail (Conyza canadensis) and fleabane (Conyza bonariensis), in vineyards. Both glufosinate-ammonium and rimsulfuron are used specifically to control these weed species.

Acres treated with plant growth regulators (PGRs) increased by 11 percent in 2008 compared to 2007. The most commonly used PGRs were gibberellins, which are applied in early spring to lengthen and loosen grape clusters. Less compact clusters may be less vulnerable to berry splitting and bunch rot. Gibberellin-treated acres increased by 13 percent in 2008.

Alfalfa

Alfalfa hay is produced for animal feed in California. The dairy industry remains the biggest market for alfalfa hay. Most counties produce some alfalfa hay, but more than half of the state’s production comes from Fresno, Kern, Imperial, Merced, and Tulare counties. Harvested alfalfa acres decreased by 4 percent in 2008 compared to 2007, but the price per ton increased by 26 percent from 2007 to 2008. The increased price for hay was due to reduced production and the high costs of grain-based animal feeds, especially in the first half of the year when the number of alfalfa shipments from other western states into California were lower than usual. The total pounds of pesticide active ingredients applied to alfalfa increased by 7 percent in 2008 compared to 2007. The acres treated with pesticides increased by 15 percent in 2008 relative to 2007.

Table 15A. Total reported pounds of all active ingredients (AI), acres treated, acres harvested, and prices for alfalfa each year from 2004 to 2008. Harvested acres from 2003 to 2007 are from CDFA, 2008; harvested acres in 2008 are from NASS, June 2009; and marketing year average prices in 2003 and 2004 are from NASS July 2005a, prices in 2005 and 2006 are from NASS, July 2007a, and prices in 2007 and 2008 are from NASS, August 2009. Acres treated means cumulative acres treated (see explanation p. 11).

 
2004
2005
2006
2007
2008
Lbs AI
2,673,263
2,862,543
3,021,455
2,909,823
3,102,080
Acres Treated
4,170,113
5,169,416
5,559,141
4,445,444
5,112,523
Acres Harvested
1,050,000
1,040,000
1,100,000
990,000
950,000
Price $/ton
$116.00
$136.00
$116.00
$165.00
$208.00

Table 15B. Percent difference from previous year for reported pounds of all AIs, acres treated, acres harvested and prices for alfalfa each year from 2004 to 2008.

 
2004
2005
2006
2007
2008
Lbs AI
-9
7
6
-4
7
Acres Treated
-14
24
8
-20
15
Acres Harvested
-4
-1
6
-10
-4
Price $/ton
25
17
-15
42
26

Figure 12. Acres of alfalfa treated by all AIs in the major types of pesticides from 1994 to 2008.
Fingure 12 

Table 15C. The non-adjuvant pesticides with the largest change in acres treated of alfalfa from 2007 to 2008. This table shows acres treated with each AI in each year from 2004 to 2008, the change in acres treated and percent change from 2007 to 2008.

AI
AI TYPE
2004
2005
2006
2007
2008
Change
Pct Change
INDOXACARB
 INSECTICIDE
122,368
337,267
481,660
246,318
386,411
140,094
57
PENDIMETHALIN
 HERBICIDE
3,982
4,578
5,820
46,138
163,172
117,034
254
LAMBDA-CYHALOTHRIN
 INSECTICIDE
215,929
230,868
247,127
255,170
358,530
103,360
41
TRIFLURALIN
 HERBICIDE
282,948
303,796
317,191
276,815
202,758
-74,057
-27
METHOXYFENOZIDE
 INSECTICIDE
 
 
5,725
330
64,337
64,008
19,426
DIURON
 HERBICIDE
204,643
157,109
186,563
148,747
100,978
-47,769
-32
CYFLUTHRIN
 INSECTICIDE
145,508
144,550
133,029
53,054
22,915
-30,139
-57
PARAQUAT DICHLORIDE
 HERBICIDE
258,297
216,114
251,477
196,254
225,894
29,640
15
4-(2,4-DB), DIMETHYLAMINE SALT
 HERBICIDE
50,436
64,028
85,443
52,879
71,085
18,206
34
IMAZETHAPYR, AMMONIUM SALT
 HERBICIDE
9,947
54,651
99,473
68,426
86,572
18,146
27
IMAZAMOX, AMMONIUM SALT
 HERBICIDE
71,896
98,113
120,149
80,894
98,659
17,764
22
CARBOFURAN
 INSECTICIDE
46,532
53,049
37,565
37,150
20,693
-16,457
-44
GLYPHOSATE
 HERBICIDE
17,292
19,930
52,114
84,867
68,594
-16,274
-19
BETA-CYFLUTHRIN
 INSECTICIDE
 
 
2,137
66,154
81,393
15,240
23
HEXAZINONE
 HERBICIDE
159,010
133,672
159,994
124,286
109,768
-14,518
-12

Statewide, insecticide use on alfalfa increased by 12 percent in pounds of AI and by 20 percent in acres treated in 2008 compared to 2007. The increase in acres treated with insecticides were mainly from increased uses of indoxacarb (57 percent), lambda-cyhalothrin (41 percent), and especially methoxyfenozide (19,000 percent) in 2008 compared to 2007. In contrast, the acres treated with cyfluthrin and carbofuran decreased by 57 and 44 percent respectively in 2008.In 2008, growers switched to products like methoxyfenozide that are have less adverse environmental impacts.

Alfalfa production requires lots of water. The uncertainty surrounding water availability and drought in California had resulted in reduced acreage and changes in management practices. Some growers choose to take fewer hay harvests than normal, pulling out the plants or allow fields to seed in lieu of irrigation. The new management practices result in changes in both insect pests dynamics and insecticides use.

Insecticide use is a reflection of the intensity of pest pressure during the season and variations with the price of hay. The statewide increase for insecticide use in pounds and acres treated may be due to more insect pressure of western yellow striped armyworm, beet armyworm, alfalfa caterpillar, and Egyptian alfalfa weevil in 2008 relative to the preceding years. Also, as the price of hay increased in early 2008, growers let the hay grow longer and sprayed for insect pests to avoid damage and get greater tonnage in lieu of early harvest. Carbofuran registration is being lost, so growers are gradually replacing it with products like indoxacarb and lambda-cyhalothrin for alfalfa weevil. Methoxyfenozide has become popular with alfalfa hay growers for worm pest control because it is not as disruptive to beneficial insects as pyrethroids. The increase in indoxacarb and methoxyfenozide was mainly in the San Joaquin and Imperial valleys, while increased use of lambda-cyhalothrin use was mainly in the Sacramento, San Joaquin, and Imperial Valleys. The decrease in cyfluthrin was predominantly in the Imperial Valley while carbofuran use decreased mainly in the San Joaquin and Imperial Valleys.

Statewide herbicide use in pounds and acres treated were relatively stable, marginally increasing by 3 and 4 percent respectively, in 2008 compared to 2007. Use of most of the 20 most highly used herbicides was stable or declined in 2008 compared to 2007, except for the use of pendimethalin, paraquat dichloride, and 2,4-DB, which increased. The increased use of paraquat dichloride may be because it is supplanting diquat dibromide, a desiccant used in seed production. The increased use of pendimethalin and 2,4-DB could be associated with the court injunction against the planting of Roundup Ready alfalfa.

The increased herbicide use in 2008 occurred mainly in the Sacramento and San Joaquin valleys whereas most of the decreased use occurred in the Imperial Valley. Although the reasons for selecting certain herbicides over others were unclear, efforts to use materials that are less likely to contaminate groundwater may have played a role in the general pattern in herbicide use.

Fungicide use in alfalfa was minimal in 2008.

Cotton

Cotton is grown for fiber, oil, and animal feed. Once one of the most widely grown crops in California, cotton acres has decreased dramatically in the last few years. Total cotton acreage decreased by 40 percent from 2007 to 2008. Two main kinds of cotton are grown: upland and Pima. Some upland cotton has also been genetically modified to be tolerant to the herbicide glyphosate (Roundup). Most cotton is grown in the southern San Joaquin Valley, but a small percentage is grown in Imperial and Riverside counties. Even less is grown in a few counties in the Sacramento Valley.

Table 16A.Total reported pounds of all active ingredients (AI), acres treated, acres planted, and prices for cotton each year from 2004 to 2008. Planted acres from 2003 to 2007 are from CDFA, 2008; planted acres in 2008 are from NASS, June 2009; Roundup Ready acres are from NASS, June 2009; and marketing year average prices from 2003 and 2004 are from NASS, July 2005a, prices from 2005 and 2006 are from NASS, July 2007a, and prices from 2007 and 2008 are from NASS, August 2009. Acres treated means cumulative acres treated (see explanation p. 11).

 
2004
2005
2006
2007
2008
Lbs AI
7,175,673
7,010,023
5,581,509
3,459,174
2,401,597
Acres Treated
10,422,661
11,416,289
9,767,050
6,306,290
4,907,648
Acres Planted Upland Cotton
560,000
430,000
285,000
195,000
120,000
Acres Planted Pima Cotton
215,000
230,000
275,000
260,000
155,000
Acres Planted Roundup-Ready
148,500
218,400
172,000
114,000
99,450
Acres Planted Total
775,000
660,000
560,000
455,000
275,000
Price Upland $/lbs
$0.56
$0.60
$0.57
$0.72
$0.56
Price Pima $/lbs
$1.01
$1.26
$1.04
$0.99
$1.14
Price All
$0.68
$0.83
$0.80
$0.88
$0.89

Table 16B. Percent difference from previous year for reported pounds of all AIs, acres treated, acres planted and prices for cotton each year from 2004 to 2008.

 
2004
2005
2006
2007
2008

Lbs AI

-2
-2
-20
-38
-31
Acres Treated
-1
10
-14
-35
-22
Acres Planted Upland Cotton
2
-23
-34
-32
-38
Acres Planted Pima Cotton
43
7
20
-5
-40
Acres Planted Roundup-Ready
0
47
-21
-34
-13
Acres Planted Total
11
-15
-15
-19
-40
Price Upland $/lbs
-26
9
-5
26
-22
Price Pima $/lbs
-18
25
-17
-5
15
Price All
-20
22
-4
9
1

Figure 13. Acres of cotton treated by all AIs in the major types of pesticides from 1994 to 2008.
Figure 13 

Table 16C.The non-adjuvant pesticides with the largest change in acres treated of cotton from 2007 to 2008. This table shows acres treated with each AI in each year from 2004 to 2008, the change in acres treated and percent change from 2007 to 2008.

AI
AI TYPE
2004
2005
2006
2007
2008
Change
Pct Change
ETHEPHON
 HARVEST_AID
572,142
563,771
487,576
385,164
243,830
-141,334
-37
DIURON
 HARVEST_AID
524,547
511,547
477,647
373,162
232,917
-140,245
-38
THIDIAZURON
 HARVEST_AID
526,341
503,099
465,903
370,921
238,120
-132,801
-36
MEPIQUAT CHLORIDE
 HARVEST_AID
553,951
653,612
583,147
338,816
208,544
-130,272
-38
UREA DIHYDROGEN SULFATE
 HARVEST_AID
343,362
366,171
317,537
266,547
154,890
-111,657
-42
ABAMECTIN
 INSECTICIDE
337,191
320,683
250,327
211,551
121,723
-89,828
-42
PARAQUAT DICHLORIDE
 HARVEST_AID
434,773
381,290
424,408
264,366
182,197
-82,169
-31
PYRAFLUFEN-ETHYL
 HARVEST_AID
129,032
332,511
362,964
292,443
212,506
-79,938
-27
PYRITHIOBAC-SODIUM
 HERBICIDE
140,874
154,014
148,330
109,630
46,157
-63,474
-58
SODIUM CHLORATE
 HARVEST_AID
341,291
243,709
187,968
109,314
46,968
-62,346
-57
GLYPHOSATE
 HERBICIDE
583,138
613,245
431,057
263,930
205,698
-58,232
-22
BIFENTHRIN
 INSECTICIDE
35,247
63,719
45,893
28,333
84,270
55,936
197
TRIFLURALIN
 HERBICIDE
231,240
200,558
159,848
96,623
43,071
-53,552
-55
OXAMYL
 INSECTICIDE
93,895
138,340
92,916
17,904
69,043
51,139
286
IPRODIONE
 FUNGICIDE
 
1,924
2,405
84
43,657
43,573
51,872

Total pesticide use on cotton decreased from 2007 to 2008, but use per acre planted increased. The increase was due to use in Kings County, where total pounds AI used, mostly insecticides, increased 8 percent. In all other major counties, pounds of AI decreased between 35 to 90 percent. The use of insecticides increased by 4 percent (acres treated) and 13 percent (pounds AI); herbicide use decreased by 34 percent (acres treated) and 31 percent (pounds AI); harvest aids, which are chemicals used to defoliate or desiccate cotton plants before harvest, decreased by 38 percent (acres treated) and 46 percent (pounds AI). Although acres treated with fungicides remained nearly the same in 2008 as in 2007, the pounds AI of fungicides decreased 17 percent.

In 2008, the insecticide applied to the greatest acreages was flonicamid, followed by abamectin, imidacloprid, indoxacarb, and bifenthrin. Use of most of the major insecticides increased above use in 2007, especially (s)-cypermethrin, lambda-cyhalothrin, and dinotefuran, all of which increased more than 600 percent. Significantly, use of cyfluthrin in Kings County increased more than 5,000 percent. However, use of many insecticides decreased, as was the case with flonicamid, abamectin, acetamiprid, aldicarb, etoxazole, thiamethoxam, oils, and methoxyfenozide. Use of flonicamid decreased only slightly (1 percent by acres treated and 3 percent by pounds of AI). Use of all miticides decreased.

Most insect and mite populations were fairly low, similar to those in 2007. Lygus bug populations, however, were major problems in some areas. Flonicamid, bifenthrin, oxamyl, cyfluthrin, (s)-cypermethrin, and lambda-cyhalothrin applications targeted lygus bugs for the most part and were all applied from mid-June through August. Lygus was a problem because safflower acreage increased and its growing season was more asynchronous and extended than usual. As the safflower matured, lygus migrated into nearby cotton fields. Alfalfa is another good host of lygus bugs, but when alfalfa is water-stressed, lygus often emigrate. Such was the case in 2008 in the water-short Lake Bottom and Corcoran areas of Kings County.

The herbicides applied to the greatest acreage of cotton in 2008 were glyphosate, pendimethalin, oxyfluorfen, pyrithiobac-sodium, and trifluralin. The only herbicide with increased use was paraquat dichloride, which was applied to 14,000 more acres than in 2007, a 100 percent increase. Again all of this increase occurred in Kings County. The largest decreases among the main herbicide by acres were pyrithiobac-sodium, trifluralin, glyphosate, flumioxazin, and oxyfluorfen. Some AIs, such as paraquat dichloride, are used both as harvest aids and herbicides. Here it is assumed if use occurred in August through November it was used as a harvest aid, otherwise as an herbicide. The decrease in herbicide use was due mostly to the decrease in acres planted.

The harvest aids that were applied to the greatest acreage were ethephon, thidiazuron, diuron, mepiquat chloride, and pyraflufen-ethyl. Although mepiquat chloride is usually included among the harvest aids, it is actually a growth regulator and is typically used mid-season. The top four harvest aids were applied to 36 percent fewer acres. Pyraflufen-ethyl had the smallest decrease in acres treated (29 percent) of nearly all harvest aids. The harvest aids with the greatest decrease were S,S,S-tributyl phosphorotrithioate (67 percent), endothall (61 percent), and sodium chlorate (57 percent). These harvest aids have been in use for many years and are being replaced somewhat by newer chemicals, such as pyraflufen-ethyl and cyclanilide, which have more predictable performance.

Fungicides are not widely used in cotton, but their use per acre planted has been trending upward because of increased problems with seedling diseases, mostly Rhizoctonia. The most commonly used fungicide both by pounds and acres treated is azoxystrobin; however, its use from 2007 to 2008 decreased by 29 percent in pounds AI and 42 percent in acres treated. The only other fungicide with any significant number of acres treated was iprodione, and its use increased dramatically from 84 acres in 2007 to 44,000 acres in 2008, nearly all of which occurred in Kings County. Azoxystrobin and iprodione are applied to cotton fields at planting to control seedling diseases. Their combined use has been high in recent years because cool spring weather was conducive to seedling diseases and because re-planting fields was nearly cost-prohibitive.

Nearly all other fungicides are used as seed treatments and are not applied to the field, so their use is reported only in pounds. Use of these seed treatments decreased except for myclobutanil, which increased by 24 percent. Nearly all myclobutanil use in 2008 occurred in Kings County.

Processing tomatoes

Processing tomato growers planted 281,000 acres in 2008, a 7 percent decrease from 2007. The highest concentration of processing tomatoes continues to be located in the southern San Joaquin Valley. Fresno County leads the state in production, with 36 percent (102,000 acres) of the statewide acres followed by Yolo County (39,000 acres), San Joaquin County (32,000 acres), and Kings County (27,000 acres).

Table 17A.Total reported pounds of all active ingredients (AI), acres treated, acres planted, and prices for processing tomatoes each year from 2004 to 2008. Planted acres from 2003 to 2007 are from CDFA, 2008; planted acres in 2008 are from NASS, January 2009; and marketing year average prices from 2003 to 2005 are from NASS, January 2006 and prices from 2006 to 2008 are from NASS, January 2009. Acres treated means cumulative acres treated (see explanation p. 11).

 
2004
2005
2006
2007
2008
Lbs AI
11,531,086
11,296,815
12,269,869
10,677,234
11,586,769
Acres Treated
2,504,906
2,777,366
2,962,484
2,683,605
2,665,731
Acres Planted
301,000
267,000
283,000
301,000
281,000
Price $/ton
$57.40
$59.60
$65.40
$70.30
$75.90

Table 17B. Percent difference from previous year for reported pounds of all AIs, acres treated, acres planted and prices for processing tomatoes each year from 2004 to 2008.

 
2004
2005
2006
2007
2008
Lbs AI
5
-2
9
-13
9
Acres Treated
-6
11
7
-9
-1
Acres Planted
4
-11
6
6
-7
Price $/ton
0
4
10
7
8

Figure 14. Acres of processing tomatoes treated by all AIs in the major types of pesticides from 1994 to 2008.

Figure 14

Table 17C. The non-adjuvant pesticides with the largest change in acres treated of processing tomatoes from 2007 to 2008. This table shows acres treated with each AI in each year from 2004 to 2008, the change in acres treated and percent change from 2007 to 2008.

AI
AI TYPE
2004
2005
2006
2007
2008
Change
Pct Change
CHLOROTHALONIL
 FUNGICIDE
94,490
101,997
114,304
140,933
78,676
-62,257
-44
TRIFLURALIN
 HERBICIDE
196,807
182,284
202,205
198,929
141,364
-57,565
-29
MYCLOBUTANIL
 FUNGICIDE
19,310
19,042
31,505
37,307
68,747
31,439
84
PYRACLOSTROBIN
 FUNGICIDE
58,385
54,581
53,634
66,297
95,629
29,332
44
DIMETHOATE
 INSECTICIDE
87,967
91,100
92,309
121,219
95,731
-25,488
-21
METHOXYFENOZIDE
 INSECTICIDE
33,893
71,046
93,152
106,233
81,312
-24,921
-23
S-METOLACHLOR
 HERBICIDE
142,195
145,364
168,950
155,503
133,106
-22,396
-14
BIFENTHRIN
 INSECTICIDE
-
-
38
7,144
29,281
22,137
310
PERMETHRIN
 INSECTICIDE
17,566
16,100
24,356
22,133
7,198
-14,935
-67
RIMSULFURON
 HERBICIDE
146,534
122,692
113,644
96,173
81,457
-14,716
-15
POTASSIUM N-METHYLDITHIOCAR-
BAMATE
 FUMIGANT
1,668
1,862
10,532
21,954
34,594
12,641
58
COPPER
 FUNGICIDE
21,096
136,762
74,214
26,846
14,931
-11,915
-44
BACILLUS THURINGIENSIS
 INSECTICIDE
53,599
60,234
32,294
27,053
15,428
-11,625
-43
MEFENOXAM
 FUNGICIDE
39,177
22,617
32,327
31,769
20,289
-11,480
-36
MANCOZEB
 FUNGICIDE
9,433
63,256
48,129
21,975
11,006
-10,970
-50

Total tons of processing tomato production in 2008 decreased by 2 percent from 2007 while pesticide use in terms of pounds of active ingredients (AI), increased by 9 percent, from 11 million pounds in 2007 to 12 million pounds in 2008. This increase in pesticide use was attributable to the onset of severe tomato powdery mildew. Similar to 2007, sulfur, metam-sodium,, and metam-potassium accounted for 85 percent of the total pounds of pesticide AI applied to processing tomatoes in 2008.

In 2008, 770,000 acres were treated with insecticides which is similar to the use in 2007. Insecticide treatments were primarily in response to pressure from aphids, lepidopterous pests (tomato pinworm and armyworms), and concerns about tomato spotted wilt virus, which is vectored by western flower thrips. Dimethoate, an inexpensive insecticide that works well for aphid control, remained the most used insecticide in pounds AI in 2008, even though use decreased by 20 percent from 2007 to 2008. Malathion had the largest percentage increase in use, increasing from only 24 pounds on 10 acres in 2007 to 3,208 pounds on 6,443 acres in 2008. This increase in use occurred because malathion became an approved insecticide for shipment of tomatoes in Mediterranean fruit fly quarantine areas of the state. Registered on tomatoes in 2007, bifenthrin is used to control mites and stinkbugs, and manage virus diseases, spotted wilt particularly. Bifenthrin use increased from 4,140 pounds on 7,144 acres in 2007 to 14,374 pounds on 29,281 acres in 2008. In contrast, the use of methoxyfenozide, permethrin, and Bacillus thuringiensis (Bt) decreased in pounds applied and acres treated. As was the case in 2007, carbaryl use increased in 2008 by 23 percent. The increased use of carbaryl is due to the appearance of ground beetles during transplanting and seedling emergence.

Acres treated with herbicides decreased by 8 percent in 2008 compared to the preceding year. Likewise, total pounds of herbicides used also decreased (7 percent). The decreases were due to a dry winter and spring that allowed cultivation. Pounds of s-metolachlor, the fifth most heavily used pesticide AI, decreased 13 percent. However, total pounds of potassium N-methyldithiocarbamate increased by 88 percent and for the first time surpassed metam-sodium (down 23 percent) as the most heavily used fumigant. Growers now prefer to add potassium rather than sodium to the soil when using this type of fumigant. The most used herbicides in 2008, both in pounds of active ingredients and acres treated include, s-metolachlor, glyphosate, trifluralin and pendimethalin. For the first time since 2002, pendimethalin use was reported because an existing pendimethalin pre-emergent residual herbicide product was approved for use on tomato in California. The availability of pendimethalin resulted in a decrease (26 percent) in trifluralin use.

One of the major issues for tomato growers in 2008 was the onset of severe tomato powdery mildew. Use of sulfur, used for russet mite and powdery mildew during May through August, increased 172,000 pounds (2 percent) in 2008 compared to 2007. However, acres treated with sulfur decreased slightly (1 percent), from 267,000 acres in 2007 to 265,000 acres in 2008. Acres treated with chlorothalonil decreased, down 62,000 acres (44 percent) from 2007 and pounds of AI applied also decreased-from 255,000 pounds in 2007 to 145,000 pounds in 2008, a 43 percent decrease. Chlorothalonil, used to control black mold primarily, but also to limit defoliation and resulting sunburn, was the most commonly used non-sulfur fungicide in 2008. Mancozeb was the next most commonly used fungicide. Even though chlorothalonil was the most used non-sulfur fungicide in 2008, its use decreased by 43 percent because other broad spectrum products were used for powdery mildew. For example, pyraclostrobin use increased by 29,332 pounds (55 percent)over use in 2007. Use of copper-based pesticides and mancozeb decreased mainly because spring weather did not favor the development of bacterial spot and bacterial speck.

Oranges

California oranges account for 27 percent of the oranges produced in the United States (US), second to Florida as the top US producing state of oranges. California’s orange production was 40 percent higher in 2008 than in 2007, but the price decreased by 19 percent due to the boost in production. Most of California oranges are grown in the San Joaquin Valley (Fresno, Kern and Tulare counties) with over half of the total in Tulare County alone. The rest are grown in the interior region (Riverside and San Bernardino counties) and on the south coast (mostly in Ventura and San Diego counties). The navel oranges were of good color, maturity, and sugar content, attributes helpful to drive consumer demand.

Table 18A.Total reported pounds of all active ingredients (AI), acres treated, acres bearing, and prices for oranges each year from 2004 to 2008. Bearing acres from 2003 to 2007 are from CDFA, 2008; bearing acres in 2008 are from NASS, September 2008; and marketing year average prices from 2003 to 2005 are from NASS, July 2006 and prices from 2006 to 2008 are from NASS, August 2009. Acres treated means cumulative acres treated (see explanation p. 11)

 
2004
2005
2006
2007
2008
Lbs AI
9,612,556
12,341,386
12,215,178
10,221,547
9,381,501
Acres Treated
2,249,087
2,627,278
2,520,099
2,396,445
2,322,494
Acres Bearing
184,000
182,000
181,000
179,000
180,000
Price $/box*
$10.72
$9.36
$10.38
$11.98
$9.68

Table 18B. Percent difference from previous year for reported pounds of all AIs, acres treated, acres bearing and prices for oranges each year from 2004 to 2008.

 
2004
2005
2006
2007
2008
Lbs AI
33
28
-1
-16
-8
Acres Treated
9
17
-4
-5
-3
Acres Bearing
-3
-1
-1
-1
1
Price $/box
43
-13
11
15
-19

Figure 15. Acres of oranges treated by all AIs in the major types of pesticides from 1994 to 2008.
Figure 15 

Table 18C. The non-adjuvant pesticides with the largest change in acres treated of oranges from 2007 to 2008. This table shows acres treated with each AI in each year from 2004 to 2008, the change in acres treated and percent change from 2007 to 2008.

AI
AI TYPE
2004
2005
2006
2007
2008
Change
Pct Change
OIL
 INSECTICIDE
202,753
205,507
196,535
200,604
146,666
-53,938
-27
SPINOSAD
 INSECTICIDE
95,971
106,022
102,534
119,426
67,634
-51,792
-43
GLYPHOSATE
 HERBICIDE
366,938
398,359
351,848
364,382
316,969
-47,413
-13
COPPER
 FUNGICIDE
163,517
234,484
240,070
163,984
199,255
35,271
22
ABAMECTIN
 INSECTICIDE
25,305
26,364
27,075
22,410
46,465
24,055
107
IMIDACLOPRID
 INSECTICIDE
12,689
4,209
13,502
11,105
33,741
22,636
204
PYRIPROXYFEN
 INSECTICIDE
44,364
41,263
43,323
57,139
40,268
-16,871
-30
ACETAMIPRID
 INSECTICIDE
8,881
5,938
3,767
23,303
12,399
-10,904
-47
RIMSULFURON
 HERBICIDE
 
 
 
154
10,399
10,245
6,653
LIMONENE
 INSECTICIDE
4,005
27,698
37,067
35,583
25,921
-9,662
-27
SIMAZINE
 HERBICIDE
93,651
101,451
81,151
74,535
65,252
-9,283
-12
2,4-D
 PLANT GROWTH REGULATOR
124,778
149,359
147,396
141,839
132,620
-9,219
-6
BETA-CYFLUTHRIN
 INSECTICIDE
 
 
 
41,872
50,527
8,655
21
DIMETHOATE
 INSECTICIDE
21,497
22,008
25,209
34,785
27,212
-7,574
-22
BACILLUS THURINGIENSIS
 INSECTICIDE
31,601
42,872
27,834
44,851
37,909
-6,943
-15

Total pounds of pesticides used decreased 8 percent from 2007 to 2008 and acres treated decreased by 3 percent. The price set per box of oranges decreased by 19 percent. The most significant decreases were in the amounts of insecticides and fungicides used. The number of bearing acres rose slightly (1 percent) which ended a downward trend that started in 2001.

The year 2008 did not have a hard freeze like the one that occurred in January 2007 that wiped out approximately 40 percent of the citrus crops. January through February 2008 was mild and warmer than usual, creating near perfect growing conditions for oranges. The summer saw high temperatures and low humidity in the citrus-growing regions. December 2008 brought low temperatures and a series of storms that negatively impacted some orange crops, but no unusual freeze events occurred.

Overall, pounds of insecticides used decreased by 33 percent from 2007 to 2008. The majority of this came from decreases in the use of horticulture oils, cryolite and malathion. Dimethoate and spinosad also had significant reduction in pounds used from 2007 to 2008. The decrease in the use of these products is most likely due to a variety of factors, such as cost, availability, exporting requirements, and pest pressures. Thrip populations were much lower in the San Joaquin Valley area during 2008 compared to previous years. Two notable pests were the Asian citrus psyllid, which arrived in California but did not have a big affect on commercial citrus in 2008, and the citrus leafminer which expanded its range north towards the San Francisco Bay Area.

Oils, spinosad, beta-cyfluthrin, abamectin, and chlorpyrifos were the insecticides used on the most acres. During 2008, oils were used to treat 146,247 acres, chlorpyrifos 43,758 acres, and spinosad, beta-cyfluthrin, and abamectin between 45,000 to 70,000 acres each. The use of oils and spinosad decreased by 27 and 43 percent respectively in 2008 compared to 2007. All five of these broad range insecticides can be used to control a variety of insects which most likely explains the large amount of acres treated with these insecticides.

Oils, chlorpyrifos, dimethoate, cryolite, and carbaryl were the most used insecticides based on pounds used. horticulture oil use decreased by 36 percent. Oils are a broad spectrum pesticide that kills soft-bodied insects such as aphids, immature whiteflies, immature scales, psyllids, immature true bugs, thrips, and some insect eggs as well as mites. Oils also control powdery mildew and other fungi. Oils can also used as an adjuvant in pesticide treatments.

Chlorpyrifos, a broad spectrum insecticide, is commonly used to control citricola scale on citrus, especially oranges. Chlorpyrifos use increased by 13 percent from 2007 to 2008. However, chlorpyrifos was used to treat 5 percent fewer acres, meaning that it was used at a higher rate of use. The rate of use may have increased due to pest resistance issues.

Dimethoate use in pounds decreased 14 percent and 22 percent in acres treated. Dimethoate is used to control a wide range of insects, including aphids, mites, thrips, plant hoppers, and white flies systemically and on contact. The decrease in dimethoate use is most likely because it is an older organophosphate pesticide product that has shown some pest resistance issues.

Pounds of cryolite used decreased by 43 percent and acres treated decreased by 40 percent. Cryolite is used on citrus crops to protect against leaf eating pests and katydids, which feeds on young fruit. The significant decrease is most likely due to the lack of availability of the insecticide and because there are more effective treatments to control target pests.

Carbaryl use decreased by 19 percent in terms of pounds applied and acres treated.

Imidacloprid-treated acres increased 200 percent and pounds applied increased by 185 percent. Imidacloprid is a systemic insecticide mostly used to control the sucking insects and leafminers on oranges. It is also used for area-wide treatment programs to reduce vectors of plant diseases, such as glassywinged sharpshooter, cotton aphid, and Asian citrus psyllid. Imidacloprid application amounts can rise and fall dramatically with these programs.

Abamectin use in terms of acres treated and pounds applied doubled from 2007 to 2008. Abamectin is primarily used as a miticide but is also effective against leafminers and leaf beetles.

Acres treated with fungicides increased by 28 percent between 2007 and 2008. That increase was primarily due to increased us of copper-based pesticides. Pounds of copper and imazalil applied during 2008 increased by 19 and 81 percent, respectively. Copper-based pesticides are the most widely used fungicides on oranges. They are used to prevent Phytophthora gummosis, Phytophthora root rot, and fruit diseases such as brown rot and Septoria spot. These diseases are exacerbated by wet weather. The increase in copper use may be related to the program to export navel oranges to Korea; the program may require one to two additional copper applications.

Acres treated with herbicides decreased by 10 percent between 2007 and 2008. Glyphosate was used the most, followed by diuron and simazine. The herbicide glyphosate is used to control weeds post-emergence. Diuron and simazine are used for pre-emergent weed control. Pounds of glyphosate and simazine applied in 2008 decreased by 10 and 11 percent, respectively; diuron use increased 5 percent. The use of the herbicide oryzalin, although used at lower amounts than glyphosate, diuron, and simazine, increased 100 percent. Paraquat dichloride use decreased by almost 44 percent. The herbicide rimsulfuron had a 6,700 percent increase in acres treated from 2007 to 2008. This large increase in acres treated is most likely due to growers trying out the new product in lieu of some of the older herbicides. Decreased use of herbicides is partially due to ground water regulations. Simazine and diuron have been identified as groundwater contaminants and human heath toxins, while paraquat dichloride is associated with acute inhalation toxicity and worker safety concerns. In addition, lower-than-average rainfall in 2008 caused reduced weed pressure resulting in relatively low herbicide use.

Rice

California’s Sacramento Valley contains more than 95 percent of the state’s rice acreage. The remainder is in north to central San Joaquin Valley. The leading rice-producing counties are Colusa, Sutter, Butte, Glenn, and Yolo. Approximately 500,000 acres in the Sacramento Valley are of a soil type restricting the crops to rice or pasture. The remainder of the acreage has greater crop flexibility.

Table 19A. Total reported pounds of all active ingredients (AI), acres treated, acres planted, and prices for rice each year from 2004 to 2008. Planted acres from 2003 to 2007 are from CDFA, 2008; planted acres in 2008 are from NASS, June 2009; and marketing year average prices in 2003 and 2004 are from NASS, July 2005a, prices in 2005 and 2006 are from NASS, July 2007a, and prices in 2007 and 2008 are from NASS, August 2009. Acres treated means cumulative acres treated (see explanation p. 11).

 
2004
2005
2006
2007
2008
Lbs AI
6,632,313
5,135,455
5,459,723
4,838,755
4,229,298
Acres Treated
2,756,203
1,996,823
2,100,371
2,292,628
2,223,562
Acres Planted
595,000
528,000
526,000
534,000
519,000
Price $/cwt
$6.95
$10.10
$11.60
$16.20
$19.30

Table 19B. Percent difference from previous year for reported pounds of all AIs, acres treated, acres planted and prices for rice each year from 2004 to 2008.

 
2004
2005
2006
2007
2008
Lbs AI
2
-23
6
-11
-13
Acres Treated
24
-28
5
9
-3
Acres Planted
17
-11
0
2
-3
Price $/cwt
-33
45
15
40
19

Figure 16. Acres of rice treated by all AIs in the major types of pesticides from 1994 to 2008.
Figure 16 

Table 19C. The non-adjuvant pesticides with the largest change in acres treated of rice from 2007 to 2008. This table shows acres treated with each AI in each year from 2004 to 2008, the change in acres treated and percent change from 2007 to 2008.

AI
AI TYPE
2004
2005
2006
2007
2008
Change
Pct Change
COPPER
 ALGAECIDE
227,340
179,268
200,000
127,024
91,395
-35,629
-28
AZOXYSTROBIN
 FUNGICIDE
167,917
108,844
105,448
139,787
172,030
32,243
23
CYHALOFOP BUTYL
 HERBICIDE
201,215
78,238
107,917
119,979
89,348
-30,631
-26
PROPANIL
 HERBICIDE
376,499
307,673
317,521
377,903
348,102
-29,801
-8
LAMBDA-CYHALOTHRIN
 INSECTICIDE
49,901
54,627
39,618
59,505
79,988
20,483
34
(S)-CYPERMETHRIN
 INSECTICIDE
30,535
21,814
38,257
48,412
30,986
-17,426
-36
FENOXAPROP-P-ETHYL
 HERBICIDE
3,989
22,572
28,253
28,099
13,887
-14,212
-51
MOLINATE
 HERBICIDE
89,593
40,535
33,044
17,471
4,276
-13,195
-76
TRICLOPYR, TRIETHYLAMINE SALT
 HERBICIDE
309,007
236,598
245,837
295,644
282,892
-12,752
-4
CLOMAZONE
 HERBICIDE
85,850
71,315
119,166
159,161
171,900
12,739
8
PENOXSULAM
 HERBICIDE
 
73,058
77,151
82,492
72,744
-9,748
-12
2,4-D
 HERBICIDE
20,960
17,914
12,893
19,946
10,356
-9,591
-48
THIOBENCARB
 HERBICIDE
136,132
118,786
79,109
74,251
65,305
-8,945
-12
MCPA, DIMETHYLAMINE SALT
 HERBICIDE
13,598
7,303
10,053
7,577
2,632
-4,945
-65
GLYPHOSATE
 HERBICIDE
26,961
17,271
11,070
6,135
1,976
-4,160
-68

Pesticide use decreased both in pounds of active ingredients applied and acres treated by 3 percent and 13 percent respectively from 2007 to 2008. Planted acres decreased by almost 3 percent. There were no major shifts in pest pressures in 2008. Herbicides were the most used pesticides accounting for 75 percent of non-adjuvant pesticide acres treated. Herbicide use decreased by 10 percent from 2007 to 2008 while insecticide and fungicide uses increased. The total acres treated with insecticides increased 14 percent and fungicides increased 10 percent in 2008 compared to 2007. Major pesticides with the largest percent increases in acres treated include lambda-cyhalothrin, azoxystrobin, and clomazone. Pesticides with the largest percentage decreases in acres treated include molinate, glyphosate, MCPA (dimethylamine salt), fenoxyprop-P-ethyl, and 2,4-D.

Lambda-cyhalothrin is the most widely used insecticide by acres treated and its use increased 34 percent in 2008 compared to 2007, at least, partly because of its low price. The price of lambda-cyhalothrin is low because it is now off patent. The price of s-cypermethrin was correspondingly dropped to compete with lambda-cyhalothrin. Both insecticides are used primarily for rice water weevil control, and secondarily for armyworm and tadpole shrimp. Insect pressure is low for California rice and these insecticides are used on only about 10 percent of planted fields Copper sulfate is also used to control tadpole shrimp, however, it is more expensive and the primary use is for algae control in rice fields. Copper sulfate also binds to organic matter such as straw residue making it less effective. Growers often rely on pyrethroids to control tadpole shrimp and rice water weevil soon after flooding. The rice water weevil is the number one rice insect pest in California rice.

Copper sulfate is the only algaecide registered for rice, and one of the few products acceptable for organic rice production. The product doubles as a control for tadpole shrimp, which is very important to organic rice growers. Copper sulfate is used in the early season when algae mats may cover fields before seedling rice breaks the water surface. Pounds of copper sulfate decreased by 25 percent because of less algal pressure at planting and a higher price of copper sulfate.

Azoxystrobin is a reduced-risk foliar fungicide. Although disease pressure is low in 2008, some growers used the product as a preventative for disease control, which increases yield.

The major herbicides in rice in 2008 in terms of acres treated were propanil, triclopyr, clomazone, cyhalofop-butyl, penoxsulam, thiobencarb, and bispyribac-sodium. Use of all of them decreased from 2007 to 2008, except for clomazone. Control of ricefield bulrush with carfentrazone has had difficulties and penoxsulam has emerged as a good control for this weed. Resistance to molinate, carfentrazone, and thiobencarb help account for the increased use of clomazone and the continued popularity of propanil. With the declining use of water-applied molinate and thiobencarb, use of foliar herbicides (cyhalofop, propanil, bispyribac-sodium, and the liquid formulation of penoxsulam) increased. Use of these herbicides require growers to lower field water levels, which in turn increases sprangletop incidence and growers’ use of cyhalofop-butyl. Glyphosate is used as a preplant herbicide in rice. The 68 percent decrease in glyphosate use probably reflects more normal weather during the planting season allowing normal spring tillage operations. However, glyphosate use can be expected to increase in the future as stale-seedbed systems (early spring seedbed preparation with no soil disturbance) become adopted for herbicide resistance management.

Head Lettuce

Head lettuce is grown in four regions in the state: the central coastal area (Monterey, San Benito, Santa Cruz, and Santa Clara counties); the southern coastal area (Santa Barbara and San Luis Obispo counties); the San Joaquin Valley (Fresno, Kings, and Kern counties); and the southern deserts (Imperial and Riverside counties). In 2004, 59 percent of all California head lettuce was planted in the central coastal area, 17 percent in the southern coastal area, 12 percent in the San Joaquin Valley, and 11 percent in the southern deserts. California produces about 72 percent of the head lettuce grown in the United States annually. In this analysis, the central and southern coastal areas are combined unless noted.

Table 20A.Total reported pounds of all active ingredients (AI), acres treated, acres planted, and prices for head lettuce each year from 2004 to 2008. Planted acres from 2003 to 2007 are from CDFA, 2008; planted acres in 2008 are from NASS, January 2009; and marketing year average prices from 2003 to 2008 are from NASS, August 2009. Acres treated means cumulative acres treated (see explanation p. 11).

 
2004
2005
2006
2007
2008
Lbs AI
1,619,139
1,826,746
1,882,444
1,713,064
1,463,664
Acres Treated
2,227,663
2,361,120
2,314,357
2,189,716
1,960,116
Acres Planted
131,000
130,000
131,000
138,000
118,000
Price $/cwt
$15.10
$15.80
$17.80
$22.00
$21.20

Table 20B. Percent difference from previous year for reported pounds of all AIs, acres treated, acres planted and prices for head lettuce each year from 2004 to 2008.

 
2004
2005
2006
2007
2008
Lbs AI
-6
13
3
-9
-15
Acres Treated
9
6
-2
-5
-10
Acres Planted
-1
-1
1
5
-14
Price $/cwt
-28
5
13
24
-4

Figure 17. Acres of head lettuce treated by all AIs in the major types of pesticides from 1994 to 2008.
Figure 17 

Table 20C. The non-adjuvant pesticides with the largest change in acres treated of head lettuce from 2007 to 2008. This table shows acres treated with each AI in each year from 2004 to 2008, the change in acres treated and percent change from 2007 to 2008.

AI
AI TYPE
2004
2005
2006
2007
2008
Change
Pct Change
SPINOSAD
 INSECTICIDE
125,190
128,716
124,997
107,120
43,989
-63,132
-59
SPINETORAM
 INSECTICIDE
 
 
 
3,543
54,740
51,198
1,445
DIAZINON
 INSECTICIDE
148,995
129,042
130,840
128,790
89,714
-39,075
-30
PERMETHRIN
 INSECTICIDE
123,483
130,178
119,665
103,428
72,369
-31,059
-30
DIMETHOMORPH
 FUNGICIDE
64,832
98,433
94,852
67,596
44,292
-23,304
-34
FOSETYL-AL
 FUNGICIDE
32,107
52,593
47,078
36,477
18,349
-18,128
-50
(S)-CYPERMETHRIN
 INSECTICIDE
92,837
107,410
114,210
104,169
87,222
-16,948
-16
METHOMYL
 INSECTICIDE
43,002
63,823
76,500
77,103
63,764
-13,340
-17
ESFENVALERATE
 INSECTICIDE
32,367
34,763
24,222
14,246
25,661
11,415
80
ACETAMIPRID
 INSECTICIDE
33,428
29,910
35,889
48,838
37,609
-11,229
-23
PROPAMOCARB HYDROCHLORIDE
 FUNGICIDE
 
 
28
74,240
63,497
-10,743
-14
PROPYZAMIDE
 HERBICIDE
76,874
76,392
79,071
72,433
61,736
-10,697
-15
FLONICAMID
 INSECTICIDE
 
 
 
2,250
12,640
10,390
462
METHOXYFENOZIDE
 INSECTICIDE
35,613
57,931
51,333
59,822
49,631
-10,191
-17
INDOXACARB
 INSECTICIDE
36,789
31,967
24,432
27,605
17,515
-10,090
-37

Pesticide use on head lettuce fluctuated from 2004 through 2008. Use of all classes of pesticide declined from 2007 to 2008. There was a 14 percent decrease from 2007 to 2008 in acres of head lettuce planted, and 2 percent decrease in acres of head lettuce harvested. Yield per acre remained the same from 2007 to 2008, but overall production decreased by 3 percent.

The major pesticides with the largest increase in acres treated were two new reduced-risk insecticides, spinetoram and flonicamid, and the pyrethroid esfenvalerate. Major pesticides with the largest decrease were spinosad, fosetyl-al, indoxacarb, dimethomorph, diazinon, permethrin, acetamiprid, methomyl, methoxyfenozide, (s)-cypermethrin, propyzamide, and propamocarb hydrochloride. During 2008, the top insecticides used (by acres treated) were imidacloprid, diazinon, (S)-cypermethrin, lambda cyhalothrin, and permethrin. The main fungicides used were maneb, propamocarb hydrochloride, dimethomorph, boscalid, and fosetyl-al. Three herbicides dominated-propyzamide (pronamide), bensulide, and benefin. Metam-potassium (potassium n-methyldithiocarbamate) was the main fumigant used, followed by metam-sodium. A total of 2 acres, which is less than 0.002 percent of total acres of lettuce planted, were treated with methyl bromide.

Insecticide use fell from 2004 to 2008. Use from 2007 to 2008, as measured by acres treated, averaged a 10 percent decline in all areas. Insecticide-treated acres decreased mostly in the inland areas-the southern deserts and San Joaquin Valley-and less so in the coastal areas. In each area, reduced-risk insecticides contributed to the total amount of insecticides used. Use of high-risk insecticides decreased overall by 15 percent:

The neonicotinoid insecticide imidacloprid is used mostly to suppress lettuce and foxglove aphids. Use of imidacloprid in the coastal area increased by 12 percent, peaking in April and August. Throughout California from 2007 to 2008, use of acephate, the popular systemic for aphids, declined in all regions.

The insecticides (S)-cypermethrin and spinosad are used to manage larvae of beet armyworm and cabbage looper, primarily pests in the southern deserts. Use of (S)-cypermethrin and spinosad, as measured by acres treated, decreased by 38 percent and 91 percent, respectively. The reduction in spinosad use was due to increased use of spinetoram, a second-generation version of spinosad. Spinetoram was used on more acres of desert lettuce than any other insecticide (over 19 thousand acres treated; spinosad was used on 3 thousand acres). In the coastal areas, use of esfenvalerate and methomyl for caterpillars increased, but decreased in the inland areas. Use of permethrin, which is primarily used for controlling seedling pests in the southern deserts such as crickets, earwigs, cutworms, and sowbugs, increased in that area by 9 percent, although seedling pest pressure was average. Permethrin use decreased in the mid-coastal area and the San Joaquin Valley, where it is used for loopers and other lepidopterous pests. Diazinon use also decreased by 61 percent in the southern deserts, where it is often used for seedling pests. Use of lambda-cyhalothrin in the central coast increased by 46 percent, probably due to high numbers of symphylans. Use of this insecticide decreased in other lettuce-growing areas.

Diazinon is a preplant treatment applied for soil pests, and until 2005 was recommended for symphylans, which show up in some coastal fields. The pyrethroids lambda-cyhalothrin and (S)-cypermethrin supposedly give better control. Use of diazinon decreased throughout the State, but increased by over 50 percent in the south coastal area. Use of S-cypermethrin decreased in all lettuce-growing areas. Insecticides such as abamectin have replaced permethrin to manage leafminers. Abamectin use in 2008 increased in the San Joaquin Valley and south coastal area due to mounting leafminer pressure.

Two new reduced-risk insecticides appeared in 2007 and became more prominent in 2008. Spinetoram, mentioned above, is effective against caterpillars, leafminers, and thrips. In 2008, its use was 55,000 acres treated. Flonicamid is a systemic that suppresses feeding by thrips and aphids, and in 2008, 10,000 acres were treated. Another reduced-risk insecticide, spirotetramat, was registered in July 2008. A systemic for aphids, its use was 16,000 acres treated. Also newly registered in May 2008 was the insecticide chlorantraniliprole, along with an insecticide that shares its diamide structure, flubendiamide.

Fungicide use by acres treated decreased by 14 percent from 2007 to 2008. Several active ingredients-both old chemistry and reduced risk, are rotated for downy mildew, a disease that has many pathovars. Maneb, used primarily to control downy mildew and prevent anthracnose, was again the dominant fungicide, as it has been every year since the early 1990s.Use of maneb declined from 2007 to 2008, as did that of dimethomorph and fosetyl-al. (See Sulfur below for powdery mildew.) Propamicarb hydrochloride, a new systemic introduced for downy mildew in 2006, is primarily used in the central coast. In 2008, its use in the coastal areas and San Joaquin Valley was second only to maneb’s. A new product containing mandipropamid was registered in June 2008, and was the fourth most-used fungicide by acres in the coastal areas to manage downy mildew.

Lettuce drop (Sclerotinia drop) is another fungal disease with a shift in popular active ingredients. Use of iprodione fell in all areas from 2007 to 2008, but rose by 3 percent in the southern deserts. Use of boscalid, a reduced-risk material, continued to rise in all lettuce-growing regions except the southern deserts. Dicloran use fell overall because of a large drop in the coastal areas; otherwise, its use increased in the inland areas. (See also chloropicrin below.) Sulfur is applied as a foliar treatment for powdery mildew. Its use decreased by 45 percent from 2007 to 2008.

Herbicide use by acres treated decreased by 14 percent from 2007 to 2008. Use of propyzamide (pronamide), applied as a postplant-preemergence herbicide, decreased statewide by 15 percent from 2007 to 2008. As consistent with its use for the past ten years, propyzamide was applied to many more acres than the preemergent, bensulide, which targets small-seeded annual grasses and is not as effective as propyzamide in the coastal areas. Use of benefin, a pre-plant herbicide popular in the San Joaquin Valley, increased from 2007 to 2008 in the middle coastal area and desert.

Nematodes are not economic pests of head lettuce, so soil is primarily fumigated to control soil-borne diseases and suppress weeds. In 2008, fumigants, mostly metam-potassium, were used on less than 3 percent of all planted lettuce acreage. Metam-potassium, like its cousin metam-sodium, is a broad-spectrum contact soil sterilant used on a handful of crops. Use of both metam-sodium and metam-potassium dropped by almost a third from 2007 to 2008. The fumigant, 1,3-dichloropropene, was used only in the San Joaquin Valley, possibly for nutsedge. Use of methyl bromide, used entirely in the coastal area, decreased by 75 percent. Chloropicrin is used to reduce soil populations of Verticillium wilt and lettuce drop alone or when combined with methyl bromide or 1,3-dichloropropene. In 2008, no chloropicrin was used on head lettuce.

Walnuts

California produces 99 percent of the walnuts grown in the United States and 66 percent of the world's production. Just over half of the walnuts produced in California are exported. In 2008, the total bearing acreage increased marginally (2 percent) from that of 2007 while the acres treated with pesticides decreased by 17 percent. The 2008 market price per ton exhibited a sharp decline of nearly 50 percent compared with that of 2007, likely due to the record large walnut harvest in 2008 (33 percent increase from 2007), combined with the global economic crisis substantially slowing demand.

Table 21A.Total reported pounds of all active ingredients (AI), acres treated, acres bearing, and prices for walnuts each year from 2004 to 2008. Bearing acres from 2003 to 2005 are from NASS, July 2006; bearing acres from 2006 to 2008 are from NASS, July 2009; and marketing year average prices from 2003 to 2008 are from NASS, August 2009. Acres treated means cumulative acres treated (see explanation p. 11).

2004
2005
2006
2007
2008
Lbs AI
2,551,681
3,812,159
3,548,919
3,984,782
3,231,532
Acres Treated
1,550,512
2,000,806
1,950,913
2,084,581
1,731,390
Acres Bearing
214,000
215,000
216,000
218,000
223,000
Price $/tons
$1,390.00
$1,570.00
$1,630.00
$2,290.00
$1,210.00

Table 21B.Percent difference from previous year for reported pounds of all AIs, acres treated, acres bearing, and prices for walnuts each year from 2004 to 2008.

 
2004
2005
2006
2007
2008
Lbs AI
-11
49
-7
12
-19
Acres Treated
-6
29
-2
7
-17
Acres Bearing
0
0
0
1
2
Price $/tons
20
13
4
40
-47

Figure 18. Acres of walnuts treated by all AIs in the major types of pesticides from 1994 to 2008.
Figure 18 


Table 21C.The non-adjuvant pesticides with the largest change in acres treated of walnuts from 2007 to 2008. This table shows acres treated with each AI in each year from 2004 to 2008, the change in acres treated and percent change from 2007 to 2008.

AI
AI TYPE
2004
2005
2006
2007
2008
Change
Pct Change
COPPER
 FUNGICIDE
144,502
283,356
187,113
234,595
135,266
-99,329
-42
MANEB
 FUNGICIDE
108,974
195,554
144,629
184,317
109,287
-75,030
-41
METHYL PARATHION
 INSECTICIDE
40,427
46,380
49,269
43,742
18,564
-25,179
-58
GLYPHOSATE
 HERBICIDE
204,592
211,224
226,920
231,481
207,015
-24,466
-11
PROPARGITE
 INSECTICIDE
56,745
67,590
64,765
50,909
29,918
-20,992
-41
GLUFOSINATE-AMMONIUM
 HERBICIDE
1,140
4,574
8,116
13,544
31,185
17,641
130
PARAQUAT DICHLORIDE
 HERBICIDE
39,710
41,007
48,507
48,551
34,883
-13,667
-28
 
 INSECTICIDE
20,526
18,292
25,784
46,867
58,097
11,230
24
CHLORPYRIFOS
 INSECTICIDE
102,775
121,904
117,602
108,538
98,689
-9,850
-9
OXYFLUORFEN
 HERBICIDE
111,154
115,038
118,722
116,304
108,594
-7,709
-7
ABAMECTIN
 INSECTICIDE
14,812
14,336
26,065
31,778
39,388
7,610
24
LAMBDA-CYHALOTHRIN
 INSECTICIDE
8,096
20,460
18,744
13,827
20,355
6,528
47
SIMAZINE
 HERBICIDE
41,283
34,280
34,839
29,029
22,731
-6,298
-22
DIURON
 HERBICIDE
30,943
29,249
30,767
22,016
16,172
-5,845
-27
SPIRODICLOFEN
 INSECTICIDE
 
 
 
6,326
11,894
5,568
88

In 2007, the most recent year of available acreage data, approximately 94 percent of walnut acreage was located in the Sacramento and San Joaquin valleys, with the remaining acreage primarily in the coastal and north eastern regions of California. In 2008, San Joaquin Valley walnuts had the highest pesticide use with a total of 1.7 million pounds of pesticide AIs used and 880,000 acres treated (includes multiple applications on the same acreage). Sacramento Valley walnuts had the next highest use, with 1.5 millions pounds AIs and 820,000 acres treated. Finally, north east and coastal region walnuts used approximately 33,000 pounds of active ingredients, with 27,000 acres treated.

The total acres treated and pounds of pesticide active ingredients decreased by 17 and 19 percent respectively in 2008 relative to the preceding year. This trend is thought to be a reflection of the reduced returns to growers caused by the low market price. In addition, continued drought reduced the need for fungicides and fumigants, as dry weather lessened the pressure of important pests such as walnut blight. Thus, acreage treated with fungicides such as copper-based pesticides and maneb and fumigants such as methyl bromide decreased by 30 to 40 percent in 2008 compared to 2007. These reductions can be environmentally significant, particularly for maneb, which has been shown to be a reproductive toxin and a carcinogen, and methyl bromide, which is associated with depletion of the stratospheric ozone layer, as well as being acutely toxic and exhibiting reproductive and developmental toxicity.

Similar to fungicides and fumigants, herbicide use also decreased in 2008 compared to that of 2007. The largest reductions were seen in the use of simazine, diuron, paraquat dichloride, glyphosate, and oxyfluorfen. Simazine and diuron are groundwater contaminants and developmental/reproductive toxins, while paraquat dichloride is associated with acute inhalation toxicity and worker safety issues. These health issues are thought to have motivated many growers to reduce use of these products. In addition, an increasing presence of glyphosate-resistant weeds may account for an 11 percent decrease in acres treated with glyphosate, as well as a 7 percent reduction in acres treated with oxyfluorfen, which is often used in conjunction with glyphosate. In contrast, glufosinate-ammonium, a newer herbicide said to be effective in controlling glyphosate-resistant weeds, showed a use increase of 128 percent in 2008 compared to 2007. Overall, growers used slightly lower amounts of products reported to be of higher risk in 2008, with little to no change in use of lower risk herbicides.

Use of insecticides also decreased in 2008, with a general shift toward use of lower risk products. Important walnut arthropod pests include codling moth, walnut husk fly, navel orangeworm, and to a lesser degree, mites and aphids. With the exception of mites, most of these pests have been traditionally controlled with organophosphates. However, accounts of negative environmental and health impacts have resulted in increasing regulations and restrictions of organophosphate use. In addition, certain pests have developed resistance to commonly used organophosphate products. Thus, increasing regulation combined with increased resistance in target pests have prompted growers to seek alternative pest control means, which is reflected in substantial decreases in the use of many organophosphates in 2008, including chlorpyrifos, methyl parathion, phosmet, naled, malathion, diazinon, and azinphos-methyl. In contrast, the acres treated with lambda-cyhalothrin, a pyrethroid, rose by 47 percent, reflecting a move toward replacing organophosphates with pyrethroid products.

In addition to increased use of some pyrethroids, there was also expanded use of lower risk alternative products in 2008, such as kaolin clay, the insect growth regulator methoxyfenozide, oils, and the botanical insecticide, neem. While spinosad, a popular alternative spinosyn, decreased in use, a new spinosyn active ingredient, spinotorem, showed a strong increase. Pheromone mating disruption exhibited a slight decrease in use from 2007, but has shown a strong upward trend since 2000.

Finally, for mite control, there has been a substantial shift away from propargite, which use is highly regulated and has a long re-entry interval due to its carcinogenicity and its acute and developmental/reproductive toxicity. A newer miticide, spirodiclofen, is thought to be effective for growers experiencing resistance issues with mites, possibly explaining the 88 percent increase in use from 2007. Reduced risk miticides, such as etoxazole, bifenazate, and oils also showed increased use in 2008, following the general trend among walnut growers toward use of lower risk pest controls.

Peaches and Nectarines

California ranks first in the United States in peach and nectarine production. In 2008 the state grew 77 percent of all peaches (including 63 percent of fresh market peaches and all of the processed peaches) and 92 percent of nectarines. Most freestone peaches and nectarines are produced in the central San Joaquin Valley, and are sold on the fresh market. Clingstone peaches, largely grown in the Sacramento Valley, are used exclusively for processing into canned and frozen products including baby food and juice. Nectarine and freestone peach acreage remained unchanged in 2008 at 31,000 acres each, while clingstone peach acreage declined from 26,500 to 25,000 acres. Peaches and nectarines are discussed together because pest management issues for the two crops are similar.

Table 22A. Total reported pounds of all active ingredients (AI), acres treated, acres bearing, and prices for peaches and nectarines each year from 2004 to 2008. Bearing acres in 2003 are from NASS, July 2005b; bearing acres from 2004 to 2005 are from NASS, July 2007b; bearing acres from 2006 to 2008 are from NASS, July 2009; and marketing year average prices from 2003 to 2008 are from NASS, August 2009. Acres treated means cumulative acres treated (see explanation p. 11).

 
2004
2005
2006
2007
2008
Lbs AI
6,439,437
6,514,894
6,793,883
5,153,494
5,356,344
Acres Treated
1,519,265
1,581,849
1,697,962
1,407,695
1,438,923
Acres Bearing
105,500
101,900
92,000
88,500
87,000
Price $/tons
$341.35
$528.50
$569.97
$440.77
$385.02

Table 22B. Percent difference from previous year for reported pounds of all AIs, acres treated, acres bearing and prices for peaches and nectarines each year from 2004 to 2008.

 
2004
2005
2006
2007
2008
Lbs AI
-1
1
4
-24
4
Acres Treated
0
4
7
-17
2
Acres Bearing
1
-3
-10
-4
-2
Price $/tons
-18
55
8
-23
-13

Figure 19. Acres of peaches and nectarines treated by all AIs in the major types of pesticides from 1994 to 2008.
Figure 19 

Table 22C. The non-adjuvant pesticides with the largest change in acres treated of peaches and nectarines from 2007 to 2008. This table shows acres treated with each AI in each year from 2004 to 2008, the change in acres treated and percent change from 2007 to 2008.

AI
AI TYPE
2004
2005
2006
2007
2008
Change
Pct Change
OIL
 INSECTICIDE
106,449
110,464
116,893
99,352
113,790
14,438
15
ESFENVALERATE
 INSECTICIDE
98,028
95,817
101,673
80,572
92,197
11,624
14
GLYPHOSATE
 HERBICIDE
141,044
143,569
152,461
126,486
116,495
-9,990
-8
SIMAZINE
 HERBICIDE
33,116
17,554
18,012
11,382
4,291
-7,091
-62
CHLORPYRIFOS
 INSECTICIDE
28,305
24,351
24,551
16,839
10,276
-6,564
-39
RIMSULFURON
 HERBICIDE
 
 
 
2
6,159
6,157
310,961
PHOSMET
 INSECTICIDE
48,084
32,253
41,204
37,782
32,179
-5,603
-15
SULFUR
 FUNGICIDE/ INSECTICIDE
105,605
104,838
102,168
76,428
70,892
-5,537
-7
CYPRODINIL
 FUNGICIDE
26,944
32,409
30,766
21,195
15,771
-5,424
-26
ORYZALIN
 HERBICIDE
11,673
13,816
16,511
12,107
6,793
-5,314
-44
FORMETANATE HYDROCHLORIDE
 INSECTICIDE
17,048
15,386
14,639
11,216
16,431
5,215
46
SPIRODICLOFEN
 INSECTICIDE
 
 
 
12,066
16,916
4,850
40
MYCLOBUTANIL
 FUNGICIDE
9,376
19,126
12,440
8,771
13,450
4,679
53
ZIRAM
 FUNGICIDE
35,472
39,451
57,398
54,144
58,629
4,485
8
FLUMIOXAZIN
 HERBICIDE
 
348
296
3,945
8,426
4,481
114

Peach and nectarine acreage treated with the major categories of pesticides has fluctuated from year to year since 1994 without substantial increasing or decreasing trends. In 2008, total acres treated with pesticides and total pounds of pesticide AI applied increased from 2007 levels by 2 percent and 3 percent respectively, even though there were 2 percent fewer bearing acres in 2008. Insect and mite outbreaks, problems with certain fungus diseases, and required treatments of large quantities of exported fruit resulted in increased applications of insecticides, miticides, fungicides, and in post-harvest fumigation. Herbicide use, however, declined. Cost-cutting and decreased weed growth due to drought may have contributed to that reduction.

Plenty of wintertime chill hours left trees ‘well rested’ before spring bloom. Fruit set was good except in orchards damaged by a late April frost. Clingstone peaches in Yuba and Sutter counties suffered the greatest yield loss. Fruit sized normally, however, and orchards that escaped the frost produced a good crop. Average clingstone peach yield per acre declined about 10 percent compared to 2007, and the price per ton increased by 12 percent. In contrast, 2008 saw the second bumper crop of freestone peaches and nectarines in a row. Record tonnage was packed for fresh market sale, continuing a situation of oversupply and falling prices. Financial hardship forced some growers and packers of nectarines and freestone peaches out of business. Overall, peach and nectarine prices decreased 13 percent in 2008. Growers were strongly motivated to cut production costs.

Total peach and nectarine acres treated with insecticides and miticides increased by about 5 percent in 2008. The warm, dry spring brought on thrips at bloom in some areas, and continuing drought favored mite infestations. The most-used active ingredients in peaches and nectarines were oils; esfenvalerate; the Oriental fruit moth (OFM) mating disruption pheromones E-8-dodecenyl acetate, Z-8-dodecenyl acetate, and Z-8-dodecenol; spinosad; and phosmet. Oils are applied during the dormant season to forestall outbreaks of scales, mites, and moth pests. Esfenvalerate is a broad-spectrum chemical that may be used in dormant applications or during the growing season, including as an alternative to OFM pheromones. Significant increases in the use of oils and esfenvalerate may be due in part to their relatively low cost. Spinosad and phosmet control moths and katydids, and spinosad is also effective against thrips. Acres treated with formetanate hydrochloride, an older, competitively priced broad-spectrum insecticide that controls thrips but triggers mite problems, and with spirodiclofen, a contact miticide, increased sharply. The jump in use of formetanate hydrochloride may be due partly to lack of a maximum residue limit (a fruit export requirement) for spinetoram, currently the main alternative for thrips control. A continuing decline in acres treated with the organophosphate insecticides chlorpyrifos and phosmet and increases in acres treated with oils and OFM pheromones suggest a trend toward reduced-risk insecticides. Reduced-risk insecticides are not more expensive than organophosphates and have shorter re-entry periods and less potential for leaving residues on fruit. Some reduced-risk insecticides that are widely used on peaches and nectarines are approved for organic production systems as well as conventional ones. Moreover, growers are being encouraged to protect water and air quality by using alternatives to conventional formulations of chlorpyrifos. Other possible reasons for the trend include residue issues with phosmet, its declining effectiveness for moth control, and a reduction in the cost of mating disruption for OFM management because longer-lasting pheromone dispensers have become available.

In 2008, peach and nectarine acres treated with fungicides increased by about 4 percent, at least in part because late May storms and cool temperatures promoted fungus growth. Problems with shot hole disease and brown rot were reported. The most-used fungicides by acres treated were sulfur, propiconazole, ziram, copper-based pesticides, iprodione, and pyraclostrobin/boscalid. Sulfur is the standard treatment for powdery mildew. Propiconazole is a low-dose chemical applied against fungi and powdery mildew. Ziram and copper-based pesticides are effective for leaf curl and shot hole disease, and ziram also controls scab. Pyraclostrobin and boscalid are reduced risk alternatives for mildew and fungus control. Acres treated with sulfur decreased significantly in 2008. Powdery mildew was not severe, and the price of sulfur went up. Applications of cyprodinil, used for brown rot, also decreased. Producers may have perceived alternatives to both sulfur and cyprodinil as being more cost-effective. Treatments with myclobutanil, a competitively priced systemic AI that controls brown rot, and with ziram, which is cheaper than copper-based pesticides for use against shot hole disease, both increased.

There was a 3 percent decrease in total peach and nectarine acres treated with herbicide in 2008. A second drought year limited weed growth and lower fruit prices motivated growers to cut costs where possible. Most-used herbicides by acres treated were glyphosate, oxyfluorfen, 2,4-D, pendimethalin, and paraquat. The use of glyphosate, simazine, and oryzalin decreased significantly. Glyphosate is becoming more costly and weed resistance to both glyphosate and paraquat is increasing, leading to greater reliance on alternatives. Simazine is a restricted-use chemical in areas prone to ground water contamination. Oryzalin is effective but expensive. In contrast, acres treated with pendimethalin continued to increase in 2008. Pendimethalin is a cheaper alternative to oryzalin. It is an effective grass herbicide with good residual control, and grass weeds can be more important during a dry spring. Use of the relatively new herbicide flumioxazin jumped, and the newly-registered AI rimsulfuron made a strong debut. Both are being promoted to growers strongly and are effective against many weeds, including some resistant species.

A reduction in total pounds of fumigant applied per acre, notable in 2007, recurred in 2008: total acres treated with fumigants increased slightly, while total pounds applied fell by about 22 percent. Growers appear to be using lower rates of most soil fumigants and/or moving from broadcast application to spot or row treatments. Those changes save money, and also respond to regulatory encouragement to reduce emissions of volatile organic compounds (VOCs), which are precursors to ground level ozone formation. The preplant fumigants 1,3-D, chloropicrin, and methyl bromide and the post-plant fumigant sodium tetrathiocarbonate accounted for 63, 18, 15, and 4 percent of peach and nectarine acres treated with soil fumigants, respectively. Acreage treated with chloropicrin went up, perhaps because it is effective in suppressing ‘replant disease’ after orchard replacement, stimulating first-year tree growth. Sodium tetrathiocarbonate treatments bounced back after dwindling almost to zero since 2004, and it was the only soil fumigant applied at a higher per acre rate during 2008. That increase may have reflected applications to control ring nematode in response to bacterial canker problems. Proposed methyl bromide applications are increasingly scrutinized because methyl bromide depletes stratospheric ozone, and it has become relatively expensive. Changing relationships between nematode infestations, rootstock choices, and application patterns also affect fumigant use and selection from year to year.

Methyl bromide is currently the only fumigant used to treat fresh peaches and nectarines in storage and for export. Post-harvest fumigant use jumped 74 percent, partly because a record crop inundated packing houses. In addition, low prices meant an exceptional amount of fresh fruit was shipped to Mexico, much of which was fumigated. Fumigation requirements may also increase if pests are detected in exported fruit upon its arrival in other countries.

Strawberries

California produces 89 percent of the total U.S. production of 2.84 billion pounds of strawberries. California produced 2.54 billion pounds valued at more than $1.54 billion. Strawberries are grown mostly for fresh market ($1.4 billion). Market prices determine the amount processed. California strawberry production occurs primarily along the central and southern coast, with smaller but significant production occurring in the Central Valley.

Table 23A. Total reported pounds of all active ingredients (AI), acres treated, acres harvested, and prices for strawberries each year from 2004 to 2008. Harvested acres from 2003 to 2007 are from CDFA, 2008; harvested acres in 2008 are from NASS, July 2009; and marketing year average prices from 2003 to 2008 are from NASS, August 2009. Acres treated means cumulative acres treated (see explanation p. 11).

 
2004
2005
2006
2007
2008
Lbs AI
9,565,451
9,227,498
9,380,340
9,641,506
9,903,124
Acres Treated
1,241,172
1,279,092
1,291,122
1,357,345
1,513,534
Acres Harvested
33,200
34,300
35,800
35,500
37,600
Price $/cwt
$62.20
$62.60
$65.10
$75.70
$75.50

Table 23B. Percent difference from previous year for reported pounds of all AIs, acres treated, acres harvested and prices for strawberries each year from 2004 to 2008.

 
2004
2005
2006
2007
2008
Lbs AI
4
-4
2
3
3
Acres Treated
-2
3
1
5
12
Acres Harvested
12
3
4
-1
6
Price $/cwt
-15
1
4
16
0

Figure 20. Acres of strawberries treated by all AIs in the major types of pesticides from 1994 to 2008.
Fingure 20 

Table 23C. The non-adjuvant pesticides with the largest change in acres treated of strawberries from 2007 to 2008. This table shows acres treated with each AI in each year from 2004 to 2008, the change in acres treated and percent change from 2007 to 2008.

AI
AI TYPE
2004
2005
2006
2007
2008
Change
Pct Change
SPINETORAM
 INSECTICIDE
 
 
 
246
32,332
32,087
13,070
SPINOSAD
 INSECTICIDE
48,590
46,420
46,855
49,814
22,804
-27,010
-54
MALATHION
 INSECTICIDE
48,708
37,523
28,460
34,528
51,217
16,689
48
BIFENTHRIN
 INSECTICIDE
13,469
14,428
19,184
25,163
41,019
15,856
63
ACETAMIPRID
 INSECTICIDE
 
 
 
 
14,033
14,033
 
OIL
 INSECTICIDE
1,378
289
477
6,431
19,009
12,577
196
MYCLOBUTANIL
 FUNGICIDE
41,156
42,506
43,221
51,487
39,516
-11,971
-23
NALED
 INSECTICIDE
22,209
20,666
18,681
23,819
33,852
10,034
42
ABAMECTIN
 INSECTICIDE
13,753
13,871
13,024
16,962
26,103
9,141
54
CAPTAN
 FUNGICIDE
149,227
174,707
151,742
127,029
135,748
8,719
7
QST 713 STRAIN OF DRIED BACILLUS SUBTILIS
 FUNGICIDE
 
379
2,485
4,861
13,441
8,580
177
FENHEXAMID
 FUNGICIDE
51,805
56,844
54,234
40,011
46,971
6,960
17
BACILLUS THURINGIENSIS
 INSECTICIDE
46,042
49,546
33,783
57,842
51,176
-6,666
-12
BOSCALID
 FUNGICIDE
28,072
52,115
56,822
55,747
62,268
6,521
12
BIFENAZATE
 INSECTICIDE
21,270
18,346
21,184
25,423
31,735
6,312
25
PYRIMETHANIL
 FUNGICIDE
 
 
30,419
16,080
22,270
6,190
38

The number of strawberry acres treated with pesticides increased 12 percent from 2007 to 2008, while acres harvested increased by 6 percent. This can in part be explained by a 4 percent increase in acres planted during this same period. Young plants were treated with pesticides but were not mature enough to be harvested until the following year. Pounds of pesticide applied increased 3 percent from 2007 to 2008 and pounds of pesticide per acre treated decreased 8 percent. Fungicides, followed by insecticides, account for the largest proportion of pesticides applied by acres treated. By acres treated, use of fungicides increased 6 percent, while insecticides increased 13 percent, while use of herbicides decreased 2 percent. The major pesticides with greatest increase in acres treated were spinetoram, malathion, bifenthrin, acetamiprid, and oils. The major pesticides with decreased use by acres treated were spinosad, myclobutanil, Bacillus thuringiensis (Bt), methomyl, and hexythiazox.

Fungicides continue to be the most used pesticides, as measured by acres treated. The most important fungal diseases of strawberries are Botrytis and powdery mildew. The major fungicides by acres treated in 2008 were captan, sulfur, pyraclostrobin, boscalid, fenhexamid, myclobutanil, cyprodinil, fludioxonil, pyrimethanil, propiconazole, and triflumizole. In general, the use of fungicides effective against Botrytis fruit rot and those effective against powdery mildew increased in 2008. The long-registered fungicides, captan, thiram, and thiophanate-methyl, fenhexamid, and boscalid, and the recently registered QST 713 strain Bacillus subtilis, and pyrimethanil are generally used to control Botrytis fruit rot. Acres treated with all of these products increased in 2008 primarily due to cool wet spring weather. Use of the biological pesticide B. subtilis continues the upward trend that began with its initial registration in 2005.

High humidity in the absence of free moisture on leaves favored development of powdery mildew in 2008. Conventional strawberry growers primarily used sulfur, myclobutanil, boscalid, pyraclostrobin, propiconazole, and quinoxyfen for its control. Sulfur is relatively inexpensive and is also used by organic growers. Sulfur, myclobutanil, potassium bicarbonate, mephanoxam, triflumizol, and azoxystrobin use decreased in 2008, while use of boscalid (up 12 percent), pyraclostrobin (up 6 percent), quinoxyfen (up 28 percent), and the newly registered propiconazole increased. The newer products are used in alternation with older fungicides to counter development of resistance and are increasingly used on summer-planted berries, which are particularly susceptible to powdery mildew. Pyraclostrobin is frequently used in combination with boscalid. Both acres treated and pounds of active ingredient applied increased with these two products in 2008. Propiconazole, registered for use on strawberries in 2008, is a fungistatic demethylation inhibitor like myclobutanil. Use of mefenoxam, effective against Phytophthora fragariae (red stele) and P. cactorum (leather rot and crown rot), decreased 33 percent in 2008. Some of the increased use of captan may have been due to is effectiveness on plant collapse pathogens, Macrophomina phaseolina and Fusarium oxysporum.

The major insect pests of strawberries are lygus bugs and worms (various moth and beetle larvae), especially in the Middle and South Coast growing areas. Until recently, lygus bugs were not considered a problem in the South Coast, but lygus has become a serious threat probably due to warmer and dryer winters and increased diversity in the regional crop complex that support this pest. The major insecticides used in 2008 by acres treated were spinetoram, malathion, Bt, bifenthrin, naled, bifenazate, methomyl, abamectin, fenpropathrin, spinosad, oils, spiromesifen and acetamiprid. Acres treated with all of these major insecticides increased except for those treated with methomyl (30 percent decrease), Bt (12 percent decrease) and spinosad (54 percent decrease). Methomyl use decreased due to the withdrawal of strawberries from the Lannate registration. Although Bt and spinosad use decreased in both the South Coast and in the Middle Coast regions they continued in 2008 to be the primary pesticides used to control worms. Bt, spinosad, and the newly registered spinetoram are biological pesticides primarily used against lepidopeteran larvae. Spinosad and spinetoram are also effective against thrips. Spinosad and spinetoram have longer residual action and are generally more effective so do not need to be applied as frequently as Bt. Spinetoram, with the same mechanism of action as spinosad, appears to have partially replaced spinosad and Bt.

Increases in lygus bug populations in the South Coast growing area and wide-spread resistance to pyrethroid pesticides led to increased use of AIs with other modes of action that are different than those of pyrethroids. These include malathion (up 48 percent), naled (up 42 percent), thiamethoxam (up 38 percent), and the newly registered acetamiprid. Products that are effective against whiteflies also increased, in particular those that contain fenpropathrin (up 21 percent), malathion, spiromesifen (up 14 percent), and bifenthrin (up 63 percent). Bt and spinosad, as well as pyrethrins (down 35 percent), are available for use by organic growers. Like Bt, pyrethrins have short residual activity and so may require multiple sprays. After increased used in 2007, both imidacloprid and pyriproxyfen use declined in 2008 by 27 percent and 45 percent respectively. Pyriproxyfen is an insect growth regulator registered in 2002.

Increased pressure from two-spotted spider mite and red spider mite pressure resulted in a 25 percent increase in the use of bifenazate, which is effective against phytophagous mites and has low toxicity to predatory mites. Bifenazate has been used by conventional strawberry growers since its introduction in 2003. In terms of acres treated, the use of other miticides increased as well: spiromesifen (20 percent), etoxazole (18 percent), acequinocyl (67 percent), and abamectin (54 percent). Acequinocyl is effective against cyclamen mite, which is not controlled by bifenazate. Hexythiazox use decreased by 16 percent. Increased mite problems may be due to a relatively warm and dry winter in 2007-2008, but may also be due to carryover of mite populations from susceptible summer-planted berries to winter-planted.

Most strawberry production relies on several fumigants. Acres treated with fumigants in 2008 remained about the same as in 2007: chloropicrin use increased 3 percent, methyl bromide use increased 5 percent, while 1,3-dichloropropene (1,3-D) use decreased 7 percent, and metam-sodium use decreased 28 percent. Chloropicrin and 1,3-D are often used together. The increase in chloropicrin use and decline in 1,3-D use is probably due to reduced availability of 1,3-D and greater efficacy of formulations with a higher ratio of chloropicrin to 1,3-D against soil borne pathogens, particularly Macrophomina and Fusarium. In Ventura county the new VOC regulations reduced the amount fumigant available to growers and township caps on 1,3-D also favored the use of higher chloropicrin formulations. Metam-sodium is generally more effective in controlling weeds, but less effective than 1,3-D or 1,3-D plus chloropicrin against soil-borne diseases and nematodes. Methyl bromide use increased in both the North East and South Coast growing areas probably because of temporarily greater availability. It was used to control pathogens and nut sedge.

Fumigants accounted for about 85 percent by weight of all pesticide AIs applied in strawberries in 2008. Fumigants are applied at high rates, in part, because they treat a volume of space rather than a surface area, such as leaves and stems of plants. Thus, the pounds applied are large relative to other pesticide types even though the number of applications or number of acres treated may be relatively small.

Carrots

California is the largest producer of fresh market carrots in the United States accounting for about 85 percent of the U.S. production of 2.5 billion pounds with a total value of $600 million in 2008. California has four main production regions for carrots: the San Joaquin Valley (Kern County); the central coast in San Luis Obispo and Santa Barbara counties (Cuyama Valley) and Monterey County; the low desert (Imperial and Riverside counties); and the high desert (Los Angeles County). The San Joaquin Valley accounts for more than half the state’s acreage.

Table 24A.Total reported pounds of all active ingredients (AI), acres treated, acres planted, and prices for carrots each year from 2004 to 2008. Planted acres from 2003 to 2007 are from CDFA, 2008; planted acres in 2008 are from NASS, January 2009; and marketing year average prices from 2003 to 2008 are from NASS, August 2009. Acres treated means cumulative acres treated (see explanation p. 11).

 
2004
2005
2006
2007
2008
Lbs AI
8,076,983
9,029,203
7,835,999
7,941,697
8,989,735
Acres Treated
503,062
535,967
453,099
523,431
590,437
Acres Planted
70,800
71,600
72,300
73,400
65,000
Price $/cwt
$21.50
$21.70
$21.10
$22.40
$25.10

Table 24B. Percent difference from previous year for reported pounds of all AIs, acres treated, acres planted and prices for carrots each year from 2004 to 2008.

 
2004
2005
2006
2007
2008
Lbs AI
-6
12
-13
1
13
Acres Treated
13
7
-15
16
13
Acres Planted
-1
1
1
2
-11
Price $/cwt
5
1
-3
6
12

Figure 21. Acres of carrots treated by all AIs in the major types of pesticides from 1994 to 2008.
Fingure 21 

Table 24C. The non-adjuvant pesticides with the largest change in acres treated of carrots from 2007 to 2008. This table shows acres treated with each AI in each year from 2004 to 2008, the change in acres treated and percent change from 2007 to 2008.

AI
AI TYPE
2004
2005
2006
2007
2008
Change
Pct Change
ESFENVALERATE
 INSECTICIDE
6,421
14,202
10,102
12,130
25,083
12,953
107
MEFENOXAM
 FUNGICIDE
102,374
97,866
82,459
77,159
87,496
10,337
13
FENAMIDONE
 FUNGICIDE
 
 
2,758
11,872
19,762
7,891
66
PENDIMETHALIN
 HERBICIDE
5
 
75
17,574
24,807
7,233
41
PYRACLOSTROBIN
 FUNGICIDE
24,732
21,765
23,938
23,844
27,393
3,549
15
IPRODIONE
 FUNGICIDE
30,054
34,159
29,414
33,657
30,364
-3,293
-10
OIL
 INSECTICIDE
2,292
6,642
1,069
1,646
4,777
3,131
190
SPINOSAD
 INSECTICIDE
3,202
2,869
1,008
1,108
4,032
2,924
264
SULFUR
 FUNGICIDE
28,092
46,235
32,527
78,574
81,404
2,830
4
CLETHODIM
 HERBICIDE
967
2,039
1,016
1,288
4,052
2,764
215
CHLOROTHALONIL
 FUNGICIDE
18,948
20,793
18,319
20,181
17,588
-2,593
-13
QST 713 STRAIN OF DRIED BACILLUS SUBTILIS
 FUNGICIDE
187
35
490
1,111
3,594
2,484
224
PYRETHRINS
 INSECTICIDE
 
142
90
2,544
205
-2,339
-92
BACILLUS THURINGIENSIS
 INSECTICIDE
3,020
1,253
837
334
2,371
2,037
609
POTASSIUM N-METHYLDITHIOCARBAMATE
 FUMIGANT
558
822
2,857
1,470
3,434
1,965
134

Total acres of carrots planted decreased by 11 percent while pesticide used (as acres treated) in carrots increased by 13 percent in 2008 compared to 2007. Pounds of pesticide active ingredients (AI) applied increased by 13 percent from 2007 to 2008. Reported use of all major pesticide types increased in terms of acres treated. Pesticides used most (as measured by acres treated) were mefenoxam, sulfur, iprodione, pyraclostrobin, esfenvalerate, pendimethalin, fenamidone, chlorothalonil, and oils. The major pesticides with increased acres treated were sulfur, pendamethalin, fenamidone, esfenvalerate, spinosad, Bacillus thuringiensis (Bt), potassium n-methyldithiocarbamate, clethodim, QST 713 strain of dried Bacillus subtilis, and oils. The major pesticides with decreased acres treated were pyrethrins, chlorothalonil, and iprodione.

Cumulatively, the most used pesticide category for carrots, as measured by acres treated, was fungicides, followed by herbicides and insecticides. From 2007 to 2008 acres treated with fungicides increased by 5 percent while pounds AI increased by 16 percent, and acres treated with herbicides increased 9 percent while pounds AI increased by 3 percent. The acres treated with insecticides increased 76 percent while pounds of AI increased by 119 percent.

The most applied fungicides in 2008 by acres treated were sulfur, mefenoxam, iprodione, pyraclostrobin, and chlorothalonil. Alternaria leaf blight, a foliar disease, is generally controlled by iprodione, chlorothalonil, pyraclostrobin, or azoxystrobin; the later two are strobilurins with the same mode of action. In terms of acres treated, iprodione use decreased 10 percent and chlorothalonil 13 percent while sulfur use increased 4 percent, pyraclostrobin increased 15 percent, mefenoxam 13 percent, and fenamidone 66 percent in 2008. Fenamidone was a new product. The organic carrot industry experienced leaf blight issues in 2008, which could explain the increased use of B. subtilis and sulfur. Carrot varieties resistant to fungal diseases are currently available which may explain the reduction of iprodione use in 2008. Cavity spot is a major, troublesome soilborne fungal disease that is commonly controlled by applying mefenoxam or metam sodium (a soil fumigant). Powdery mildew is primarily controlled by sulfur, which is inexpensive and especially popular with organic growers. Sulfur use increased in 2008 because weather conditions favored powdery mildew infection.

In terms of acres treated, the main herbicides used in carrot production were linuron, pendimethalin, trifluralin, fluazifop-p-butyl, and clethodim. The use of linuron, a postemergence herbicide that provides good control of broadleaf weeds and small grasses, increased 2 percent. Trifluralin, a preemergence herbicide, complements linuron for weed management; its use increased by 4 percent. Pendimethalin use increased by 41 percent, possibly because it inhibits carrot root development less than other herbicides. In addition, fluazifop-p-butyl, a selective postemergence phenoxy herbicide used for control of annual and perennial grasses, decreased by 5 percent.

Most carrot production relies on the fumigants metam sodium, 1,3-D, potassium n-methyldithiocarbamate (metam-potassium), and to a lesser extent, chloropicrin. These fumigants are used to manage nematodes and may provide other benefits such as weed and soil borne disease control. In 2008, fumigants accounted for about 74 percent of the total pounds of pesticide AIs applied to carrots. This is a 13 percent increase from 2007. Also, acres treated with fumigants increased by 8 percent. The number of acres treated with metam-sodium, metam-potassium, and chloropicrin increased (8, 134, and 81 percent acres treated, respectively), while those treated with 1,3-D decreased by 14 percent. At low to moderate levels of nematode infestation, metam-sodium or metam-potassium is usually used. If nematode levels are high, 1,3-D is preferred. 1,3-D usage decreased (14 percent) in 2008 compared to 2007, probably because of regional demand based on nematode populations and the effects of local use limits established to mitigate air quality concerns.

Insects are not generally major problems in carrot production, except for whiteflies, which are controlled with esfenvalerate and methomyl. The major insecticides used in 2008 in terms of acres treated were esfenvalerate, oils, spinosad, diazinon, cyfluthrin, and methomyl. Acres treated with esfenvalerate increased by 107 percent in 2008 compared to 2007. Major infestations of crown root aphid in 2008 could explain the increased use of esfenvalerate and spinosad. Although generally used against whitefly, they are also used to control flea beetle, leafhoppers and cutworms. Acres treated with methomyl decreased in 2008. This carbamate pesticide is effective against cutworms and leafhoppers as well as whiteflies. Diazinon use against cutworms and wireworms also decreased. The use of oils, used as an insecticide , increased by 190 percent. Cyfluthrin, a pyrethroid used to control cutworm and crown root aphids, increased by 175 percent while pyrethrins, used against a wide range of pests, decreased 92 percent in 2008.

Sources of Information

Adaskaveg, J., Gubler, D., Michailides, T, and B. Holtz. 2009. Efficacy and Timing of Fungicides, Bactericides, and Biologicals for Deciduous Tree Fruit, Nut, Strawberry, and Vine Crops. UC Davis, Department of Plant Pathology; Statewide IPM Program; and UC Kearney Agricultural Center. Linked to Pest Management Guidelines on the UC IPM Web site.

Almond Board of California.

Blue Diamond Growers.

Boriss, H., H. Burnke, and M. Kreith. 2009. English Walnuts Profile, AgMRC, Agricultural Marketing Resource Center.

California Canning Peach Association online “Facts and Research”

California Department of Food and Agriculture (CDFA), 2008. California Agriculture Resource Directory 2007.

California Farm Bureau. 2008. Ag Alert. Weekly newspaper, various issues.

California Tree Fruit Agreement Annual Report 2008.

County Agricultural Commissioners

Growers

NASS. July 2004. Agricultural Prices 2003 Summary. USDA. Pr 1-3 (04).

NASS, January 2005, Vegetables 2004 Summary. USDA. Vg 1-2 (05)

NASS, July 2005a, Agricultural Prices 2004 Summary. USDA. Pr 1-3 (05)a.

NASS, July 2005b, Noncitrus Fruits and Nuts 2004 Summary USDA. Fr Nt 1-3 (05)

NASS, July 2006, Agricultural Prices 2005 Summary. USDA. Pr 1-3 (06).

NASS, July 2007a, Agricultural Prices 2006 Summary. USDA. Pr 1-3 (07).

NASS, July 2007b, Noncitrus Fruits and Nuts 2006 Summary USDA. Fr Nt 1-3 (07)

NASS, July 2008, Agricultural Prices 2007 Summary. USDA. Pr 1-3 (08)a.

NASS, September 2008, Citrus Fruits 2008 Summary. Fr Nt 3-1 (08)

NASS, January 2009, Vegetables 2008 Summary. Vg 1-2 (09)

NASS, March 2009, California Grape Acreage Report 2008 Summary

NASS, May 2009. 2008 California Almond Acreage Report

NASS, June 2009. Acreage. Cr Pr 2-5 (6-09)

NASS, July 2009, Noncitrus Fruits and Nuts 2008 Summary. Fr Nt 1-3 (09)a

NASS, August 2009, Agricultural Prices 2008 Summary. Pr 1-3 (09)a.

Pest Control Advisors

PPN Network Connection. 2008. Online newsletter of the California Tree Fruit Agreement. Various issues.

Private Consultants

University of California Cooperative Extension Area IPM Advisors

UC Cooperative Extension Farm Advisors

UC Cooperative Extension Specialists

UC Researchers

USDA, Fruit and Tree Nuts Outlook/FTS-332/May 29, 2008. Economic Research Service

Welch, William and Alan Gomez, “Cold Snap Threatens California Citrus Crop”, USA Today, December 16, 2008.

Western Farm Press. 2008. Newspaper published two or three times per month, various issues.



VI. SUMMARY OF PESTICIDE USE REPORT DATA 2008 INDEXED BY CHEMICAL

The following report presents information of statewide pesticide use for 2008. For each chemical, the commodity on which it was used, total pounds applied, the number of agricultural applications made, and the amount of commodity treated are summarized.

A summary by commodity is presented in a separate report, Summary of Pesticide Use Report Data 2008 Indexed by Commodity. Both versions of the Pesticide Use Report are available on a cd (send requests to mwilliams@cdpr.ca.gov, can be found on DPR’s Web site, or can be downloaded from DPR’s FTP site.