October 2003

Any portion of this report may be reproduced for any but profit-making purposes.
For information on purchase of additional copies or of electronic data files, see order form on Page ii.
This report is also available on DPR's Web site <www.cdpr.ca.gov>.
If you have questions concerning this report, call (916) 445-4100.

Table of Contents

Order Form

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 2002 Indexed by Commodity This link downloads the compressed ASCII version. This version does not include figures. See UNZIP HELP)

Order Information

To continue to make the Summary of Pesticide Use Report Data available, it is necessary to charge for the costs of reproduction and mailing. The reports can also be downloaded free of charge from the Department's web site (www.cdpr.ca.gov).

The 1989 - 2002 Summary of Pesticide Use Report Data indexed by chemical or commodity reports can be found on DPR's web at www.cdpr.ca.gov. The Annual Pesticide Use Report Data (the complete database of reported pesticide applications for 1990-2002) are available on CD ROM. The files are in text (comma delimited format).

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.

I. INTRODUCTION

Development and Implementation of the Pesticide Use Reporting System

This 2002 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 and 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 data may be obtained from DPR for in?depth, analytical purposes.

To provide public access to the data as soon as possible, DPR is releasing the 2002 data before the majority of error corrections have been completed. Values have been substituted for some errors (see Outliers), but data correction is ongoing.

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. The main exceptions to full use reporting are home and garden applications, and most industrial and institutional uses. Pesticide use reporting is explained in more detail below.

To enhance accuracy of the data, DPR contracts with agricultural commissioners in the state's 58 counties for the electronic submittal of their pesticide use data. To further improve the accuracy and timeliness of pesticide use data, DPR initiated the California Electronic Data Transfer System (CEDTS) in 1994. This system allows growers and pest control operators to electronically transfer application data to the agricultural commissioners' offices. By the close of 1998, 36 counties were capable of receiving data through the CEDTS program. Although response to CEDTS from pesticide users was favorable, adoption of the reporting system was slow. Many growers and pest control operators lack the time and expertise to write the software that pulls together the necessary pieces of information into a single pesticide use application database that meets DPR's standardized data requirements. In response, private software providers and others began introducing systems that allow use reporting via Internet Web sites in 1999. In addition, new programs are being developed to allow nonagricultural users of pesticides to file electronic reports.

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 hazard to public health, farm workers, domestic animals, honeybees, the environment, wildlife, or other crops. Restricted materials, with certain exceptions, 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 the county agricultural commissioner.

In addition, the State required commercial pest control operators (those in the business of applying pesticides, such as agricultural applicators, structural fumigators, and professional gardeners) 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.

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 demanding 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, 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 reporting regulations, pest control operators must give farmers a written notice after every pesticide application that includes the date and time the application was completed, and the reentry and preharvest intervals (respectively, the intervals between the time a pesticide is applied and when workers may enter the field, and the time of application and when a commodity can be harvested). 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 helps scientists estimate typical applications and how often pesticides are used.

Public Health

The expanded reporting system provides DPR and the State Department of Health Services with complete pesticide use data for evaluating possible human illness clusters in epidemiological studies.

Endangered Species

DPR is working with the 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 when 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

In meeting the requirements of the Pesticide Contamination Prevention Act of 1985, site-specific records 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.

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.

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.

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.

DPR manages several grant programs, pending availability of funding, to support projects to develop, implement, and demonstrate reduced-risk pest management strategies. (Due to a statewide budget shortfall, no money is available to fund new projects for fiscal year 2003/2004.) One of these programs is the Pest Management Alliance Grants. This program provides grant money to growers, commodity boards, farm advisors, urban site representatives, researchers, and government to identify critical pest management needs, environmental or human exposure issues resulting from pesticide use, and to develop a program to solve the critical problems. To help the groups in their evaluations of current pest management practices, DPR provides data on use of all pesticides on the Alliance crop or site. DPR and other funding agencies can also use the PUR to help evaluate the effectiveness of the programs they have funded.

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 reports include summary trends of pesticides in several different categories such as carcinogens, reproductive toxins, and ground water contaminants.

Processor and Retailer Requirements

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 product 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, bins, etc.)

Commodity Codes

III. DATA SUMMARY

Pesticide Use In California

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). Five counties in this region had the highest use: Fresno, Kern, Tulare, San Joaquin, and Madera.

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.

There were approximately 598 million pounds of pesticide active ingredients sold in California in 2002, 563 million pounds in 2001, 601 million pounds in 2000, 707 million pounds in 1999, 617 million pounds in 1998, 645 million pounds in 1997, 639 million pounds in 1996, 543 million pounds in 1995, and 625 million pounds in 1994. Prior years data are posted on DPR's web site at www.cdpr.ca.gov under programs & services/mill assessment/report of pesticides sold in CA.

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 and amount of pounds used without indicating an increased reliance on pesticides.

Table 1. Total pounds of pesticide active ingredients reported in each county during 2001 and 2002 and its rank among all 58 counties.

*Note: Not all of Kern County PUR data was available in 2001.

Table 2. Pounds of pesticide active ingredients, 1992 - 2002, by general use categories.

* 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.

USE TRENDS OF PESTICIDES ON THE STATE'S PROPOSITION 65 LIST OF CHEMICALS THAT ARE "KNOWN TO CAUSE REPRODUCTIVE TOXICITY"

Table 3B. 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 includes both agricultural and nonagricultural applications. The reported cumulative acres treated includes 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"

USE TRENDS OF CHOLINESTERASE-INHIBITING PESTICIDES

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

USE TRENDS OF PESTICIDES ON DPR'S GROUNDWATER PROTECTION LIST

Table 6A. The reported pounds of pesticides on DPR's ground water protection list. These pesticides are the currently registered active ingredients listed in section 6800(a) of the California Code of Regulations, Title 3, Division 6, Chapter 4, Subchapter 1, Article 1. Use includes both agricultural and reportable nonagricultural applications. Data are from the Department of Pesticide Regulation's Pesticide Use Reports.

Table 6B. The reported cumulative acres treated in California with pesticides on DPR's ground water protection list. These pesticides are the currently registered active ingredients listed in section 6800(a) of the California Code of Regulations, Title 3, Division 6, Chapter 4, Subchapter 1, Article 1. 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 4. Use trends of pesticides on DPR's ground water protection list. These pesticides are the currently registered active ingredients listed in section 6800(a) of the California Code of Regulations, Title 3, Division 6, Chapter 4, Subchapter 1, Article 1. Reported pounds of active ingredient (AI) applied includes both agricultural and reportable nonagricultural applications. The reported cumulative acres treated includes primarily agricultural applications. Data are from the Department of Pesticide Regulation's Pesticide Use Reports.

USE TRENDS OF PESTICIDES ON DPR'S TOXIC AIR CONTAMINANTS LIST

Table 7A. The reported pounds of pesticides on DPR's toxic air contaminants list applied in California. These pesticides are the currently registered 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 7B. The reported cumulative acres treated in California with pesticides on DPR's toxic air contaminants list. These pesticides are the currently registered 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 currently registered 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 includes both agricultural and reportable nonagricultural applications. The reported cumulative acres treated includes primarily agricultural applications. Data are from the Department of Pesticide Regulation's Pesticide Use Reports.

USE TRENDS OF OIL PESTICIDES

Table 8A. 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 nonagricultural applications. Data are from the Department of Pesticide Regulation's Pesticide Use Reports.

Table 8B. 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 8A.) Uses include primarily agricultural applications. Data are from the Department of Pesticide Regulation's Pesticide Use Reports.

Figure 6. 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 includes both agricultural and reportable nonagricultural applications. The reported cumulative acres treated includes primarily agricultural applications. Data are from the Department of Pesticide Regulation's Pesticide Use Reports.

USE TRENDS OF REDUCED-RISK PESTICIDES

Table 9A. The reported pounds of reduced-risk pesticides applied in California. These active ingredients are contained in pesticide products that have been given reduced-risk status by U.S. EPA. Use includes both agricultural and reportable nonagricultural 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 9B. . The reported cumulative acres treated of reduced-risk pesticides in California. These active ingredients are contained in pesticide products that have been given reduced-risk status by U.S. EPA. Use includes primarily 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.

Figure 7. . Use trends of reduced-risk pesticides. These active ingredients are contained in pesticide products that have been given reduced-risk status by U.S. EPA. Reported pounds of active ingredient (AI) applied includes both agricultural and reportable nonagricultural applications. The reported cumulative acres treated includes primarily agricultural applications. Data are from the Department of Pesticide Regulation's Pesticide Use Reports.

USE TRENDS OF BIOPESTICIDES

Table 10A. 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 reportable nonagricultural 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 10B. The reported cumulative acres treated 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 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 includes both agricultural and reportable nonagricultural applications. The reported cumulative acres treated includes 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 2001 to 2002 for the following commodities: (1) cotton, (2) wine grapes, (3) table and raisin grapes, (4) almonds, (5) alfalfa, (6) rice, (7) processing tomatoes, (8) head lettuce, (9) oranges, (10) peaches and nectarines, (11) walnuts, (12) leaf lettuce, (13) strawberries, and (14) carrots. These commodities were chosen because they had the greatest pesticide use by acres treated or were of particular interest to DPR.

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

Reported pesticide use in California in 2002 totaled 172 million pounds, an increase of 21 million pounds from 2001 (14 percent). The active ingredients with the largest uses by pounds were sulfur, petroleum oils, metam-sodium, and methyl bromide. Sulfur use increased by 6.5 million pounds (14 percent) and was the most highly used pesticide in 2002, both in pounds applied and acres treated. By pounds, sulfur accounted for 31 percent of all reported pesticide use. Sulfur is a natural fungicide favored by both conventional and organic farmers. Petroleum oil use increased by 2.3 million pounds (15 percent), metam sodium use increased by 4.2 million pounds (37 percent), and methyl bromide use declined by approximately 21,000 pounds (0.3 percent).

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. For the majority of the 14 crops investigated, pest problems were low in most areas in 2002. Prices for some crops improved in 2002 but, in general, economic conditions for growers were a major concern. Acreage of most of the 14 crops increased, which would explain some of the increase in pesticide use.

Sulfur was used mostly on grapes and use increased because of greater grape acreage and lower grape prices. Sulfur is also less costly than other fungicides.

Most of the increase in pounds of active ingredients occurred with the fumigants. The use of the fumigants metam sodium and 1,3-dichloropropene (1,3-D) increased partly as replacements for methyl bromide, use of which decreased. More than half of the methyl bromide was used on strawberries; use decreased probably because of the expanded restrictions that DPR placed on field applications in the last few years and because a federally mandated phaseout has significantly increased the cost of methyl bromide.

Different pesticides are used at very 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.

By acres treated, the pesticides with the greatest use in 2002, after sulfur, were glyphosate, oxyfluorfen, and paraquat dichloride, all herbicides. Herbicides aaccounted for most of the increase in acres treated from 2001 to 2002. Most of the increase in glyphosate and oxyfluorfen was in almonds and wine grapes. Use of glyphosate increased because of a trend toward more use of postemergence herbicides and because it is less costly than other herbicides. Oxyfluorfen is often applied with glyphosate.

Use is given by pounds of active ingredient 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 one acre is treated three times in a season with an individual active ingredient, it is counted as three acres treated).

Cotton

Cotton is grown for fiber, oil, and animal feed. Even though cotton acreage has decreased significantly in recent years, it is still one of the most widely grown crops in California. Most cotton is grown in the southern San Joaquin Valley, but a small percentage is grown in the Imperial and Sacramento valleys.

Table 11A. Total reported pounds of all active ingredients (AIs), acres treated, acres planted, and prices for cotton each year from 1998 to 2002.

Table 11B. Percent difference from previous year for reported pounds of all AIs, acres treated, acres planted, and prices for cotton from 1998 to 2002.

Figure 9. Acres treated in cotton by all active ingredients in the major types of pesticides from 1993 to 2002.

The major insecticides by acres treated in cotton in 2002 were avermectin, chlorpyrifos, aldicarb, thiamethoxam, and dicofol; the major herbicides were glyphosate, trifluralin, pendimethalin, oxyfluorfen, and pyrithiobac-sodium; and the major harvest aids were paraquat dichloride, ethephon, mepiquat dichloride, sodium chlorate, and diuron. The use of most pesticides declined. Some of the major exceptions were increases in avermectin, thiamethoxam, endosulfan, pyriproxyfen, buprofezin, trifluralin, pyrithiobac-sodium, clethodim, and endothall.

In 2002, weather conditions for cotton production were excellent, and pest levels were unusually low. Lygus bug, which is one of the major cotton pests, had very low populations in most areas. Spider mites caused little problems in most areas. Lepidopteran pests were also very low. The main concerns were silverleaf whiteflies and aphids near the end of the cotton-growing season. These pests are of particular concern because they produce sugary excretions, which drop on the cotton lint creating "sticky cotton." The California cotton industry was concerned because sticky cotton was a major problem in 2001, and other countries threatened to discount California cotton unless they could be assured that the cotton would be clean. Therefore, in 2002, growers were aggressive in controlling whiteflies and aphids.

The other major factor in understanding trends in pesticide use is that cotton acreage has declined in the last few years, reaching the lowest acreage since 1946. Growers are planting less because of low cotton prices, high electricity costs, and uncertainty of the water supply. Many cotton growers replanted their acreage with permanent crops, so they could not quickly switch back to cotton even though cotton prices were higher in 2002.

Most of the insecticides which had a higher use in 2002, such as thiamethoxam, endosulfan, pyriproxyfen, and buprofezin were used for whitefly or aphid control near the end of the season. Thiamethoxam was a new reduced-risk pesticide, first used in cotton in 2002. Pyriproxyfen and buprofezin are insect growth regulators specific to whiteflies. Avermectin use was slightly higher in 2002 than 2001. It is used to control mites, and its use increased probably not so much because of greater mite problems but as a replacement for older miticides, which are becoming less effective.

Herbicide use decreased but less than the decrease in acres planted, implying an increase in use per acre planted. The primary increase was in trifluralin, which is used as a preplant treatment of cotton fields. Growers used more trifluralin in 2002 because of their experience with Roundup-Ready cotton, which is resistant to the herbicide glyphosate. One of the reasons some growers planted Roundup-Ready cotton was to reduce their use of preplant herbicides and increase their use of glyphosate during the growing season. However, they found that some weeds could not be controlled by glyphosate so they returned to the older practice of using preplant trifluralin. The use of the herbicide pyrithiobac-sodium increased probably because growers found it to be effective for some weeds.

Use of harvest aids was down because weather conditions in 2002 made cotton easier to defoliate. Also, growers are switching from high rate defoliants, such as S,S,S-tributyl phosphorotrithioate and sodium cacodylate to chemicals such as diuron and thidiazuron, which are used at lower rates.

Wine grapes

There are four major wine grape production regions in California: 1) North Coast (Lake, Mendocino, Napa, and Sonoma counties) with about 10 percent of the statewide wine grape production; 2) Central Coast (Alameda, Monterey, San Luis Obispo, Santa Barbara, San Benito, Santa Cruz, and Santa Clara counties) with about 8 percent of the wine grape production; 3) Northern San Joaquin Valley (San Joaquin, Calaveras, Amador, Sacramento, Merced, Stanislaus and Yolo Counties) with about 20 percent of the wine grape production; and 4) Southern San Joaquin Valley (Fresno, Kings, Tulare, Kern, and Madera counties) with about 60 percent of the wine grape production. Each region has distinct climatic and geologic characteristics that lead to different cultural and pest management practices.

Table 12A. Total wine grape acres planted, reported pounds of all AIs, acres treated, and prices for wine grapes each year from 1998 to 2002.

Table 12B. Percent difference from previous year for wine grape acres planted, reported pounds of all AIs, acres treated, and prices for wine grapes from 1998 to 2002.

Figure 10. Acres treated in wine grapes by all active ingredients in the major types of pesticides from 1993 to 2002.

The major fungicides by acres treated in wine grapes in 2002 were sulfur, copper hydroxide, myclobutanil, trifloxystrobin, and tebuconazole. The major insecticides and miticides were imidacloprid, tebufenozide, propargite, avermectin, and pyridaben. The major herbicides were glyphosate, oxyfluorfen, paraquat dichloride, simazine, and diuron. Pesticides with large percentage increases in acres treated include lime-sulfur, diuron, tebuconazole, trifloxystrobin, myclobutanil, oxyfluorfen, and glyphosate. Those with large decreases in use include mancozeb, propargite, azoxystrobin, avermectin, fenarimol, imidacloprid, and copper hydroxide.

In 2002, the major factors influencing pesticide use changes include pest pressure (which varied by region); low grape prices (hence the need for growers to reduce costs); competition from newer products; and continued increasing emphasis on sustainable farming. Buyer restrictions and reduced pest pressure contributed to the decreased use of certain fungicides and insecticide/miticides.

Most fungicide use was for control of powdery mildew. Rainfall was moderate in 2002, and disease mildew pressure was not especially high in the valley regions, although the Central Coast region reported high disease pressure. Fungicide use by acres treated in 2002 increased by 4 percent. A small change in mildew pressure can easily result in a change in fungicide use. Low grape prices resulted in decreased use of the more costly treatment alternatives and the increased use of the less expensive alternatives (e.g., sulfur, myclobutanil, and lime-sulfur). The use of lime-sulfur as a dormant treatment contributed to its large increase. Benomyl use significantly decreased because of it is not available and growers are using only inventory on hand.

Insecticide and miticide use decreased by 14 percent due mainly to reduced pest pressure from worms and mites. Economic considerations (e.g., fewer growers treated for grape leafhopper and bluegreen sharpshooter) and market competition from newer products contributed to the declining use of several of the top insecticides and miticides (such as imidacloprid, avermectin, pyridaben, and cryolite). Growers' increasing emphasis on sustainable farming practices was another major factor accounting for declining uses. Buyer restrictions also contributed to use reductions in certain products such as cryolite and propargite. Some of the largest decreases were imidacloprid (for leafhoppers, sharpshooters, and mealybugs); propargite, avermectin, and pyridaben (for spider mites); cryolite (for omnivorous leafroller); methomyl (for leafhoppers, spider mites, and omnivorous leafroller); and Bt (for omnivorous leafroller and other Lepidoptera).

A major contributor to the 12 percent increase in herbicide use was the increased use of less costly herbicides and the increased use of postemergence herbicides, particularly glyphosate, in place of preemergence herbicides. Glyphosate usually requires several applications in contrast to one application for preemergence herbicides. The continued limited availability of oryzalin (due to a manufacturing plant explosion in 2000) was one reason for the increased use of oxyfluorfen for weed control; another reason was the increased use of glyphosate + oxyfluorfen, including the use of a new product that combines these AIs.

Although norflurazon is registered to control nutsedge in grapes, it is not very cost-effective where large populations occur. Therefore, many growers have moved to other less expensive herbicides like glyphosate. A less expensive generic oryzalin product was released into California for the 2002 season, and growers took advantage of the cost savings over the original product. Since its tank-mix partner is typically oxyfluorfen, this may help explain the significant increase in use of both herbicides. The increase in simazine and diuron may be explained by use of these herbicides in inexpensive tank-mix combinations that can control a wide spectrum of weeds that the other pre- and post-emergence herbicides miss.

Table grapes and raisins

Production of table grapes is largely centered in the Southern San Joaquin Valley region (85%), although a significant portion of production (14 percent) comes from the Coachella Valley region. The Southern San Joaquin Valley region includes Fresno, Madera, Tulare, Kern, and Kings counties; the Coachella Valley region includes the Coachella regions of Riverside, Imperial, and San Bernardino counties. The remaining regions account for less than 1 percent of the state's production. Almost all (99 percent) production of raisin grapes is in the Southern San Joaquin Valley region, and 1 percent in the Northern San Joaquin Valley region (San Joaquin, Calaveras, Amador, Sacramento, Merced, and Stanislaus counties.

Table 13A. Total table grape and raisin acres planted, reported pounds of all AIs, acres treated, and prices for grapes each year from 1998 to 2002.

Table 13B. Percent difference from previous year for table grape and raisin acres planted, reported pounds of all AIs, acres treated, and prices for grapes from 1998 to 2002.1998 to 2002.

Figure 11. Acres treated in table grapes and raisin by all active ingredients in the major types of pesticides from 1993 to 2002.

The major insecticides and miticides by acres treated in table and raisin grapes in 2002 were cryolite, imidacloprid, tebufenozide, propargite, and chlorpyrifos; the major herbicides were glyphosate, paraquat, simazine, oxyfluorfen, and diuron; and the major fungicides were sulfur, myclobutanil, copper hydroxide, tebuconazole, and trifloxystrobin. Pesticides with large increases in use include tebufenozide, trifloxystrobin, cyprodinil, oxyfluorfen, paraquat, and sulfur. Those with large decreases in use include benomyl, imidacloprid, propargite, myclobutanil, and cryolite.

Most of the highest use fungicides were used for powdery mildew control. Total pounds of fungicide increased, however not all major uses increased. Reasons contributing to increased use were the use of lower-cost alternatives (e.g., sulfur, myclobutanil, and lime-sulfur) and preference for newer materials such as tebuconazole and trifloxystrobin. Weather in 2002 was not particularly wet, and disease pressure was not a major reason for increases in use. Reasons for the decreased use of certain fungicides include efforts by growers to reduce costs due to lower crop prices, lower pest pressure, and competition from other products. The large decrease in use of benomyl is due to its unavailability.

Overall, use of insecticides and miticides decreased. Cryolite use decreased in part due to competition from other pesticide alternatives for control of lepidopteran pests and because of restrictions from buyers. Cryolite is used to control omnivorous leafroller and other Lepidopteran pests. Imidacloprid use decreased by 24 percent, mainly because of decreased pest pressure. Imidacloprid is used primarily for control of leafhoppers, mealybugs, and sharpshooters. Propargite decreased mainly due to competition from newer miticides, its long re-entry interval, restrictions from buyers, and cost. Propargite is used for control of spider mites. Methomyl use decreased due to cost and regulatory status (a highly toxic Category 1 pesticide). Acres treated with the nematicide fenamiphos increased, mainly due to greater pest pressure and because of the higher cost and use restrictions of pre-plant methyl bromide. Young vineyards were hit hard by nematodes, especially those planted without fumigation. Nematode problems were more apparent in vineyards with deficit irrigation.

Herbicide use increased overall, although no very large increases in individual herbicides occurred. The poor economic environment had a major impact on the way weed control options were selected. The very poor demand in raisin grapes has probably overshadowed any effect table grape production may have played on herbicide selection. For the most part, many growers who used other, more expensive options in the past have opted for cheaper alternatives, even if it meant not achieving complete weed control. Among the most affordable herbicides (and highest uses) in table and raisin grapes are glyphosate, paraquat, and simazine. The weed pests marestail and hairy fleabane are fast becoming a significant problem in vineyards in the San Joaquin Valley. Additional sprays of glyphosate and paraquat are often needed to control these weeds. Simazine is probably the most effective; therefore, simazine is used more often to handle these specific weeds, even in areas that have not previously been treated for them. Oxyfluorfen is now almost always added to glyphosate to help control these weeds, which may help explain the oxyfluorfen increase.

Almonds

California is the only state that commercially produces almonds. Over the last several years California has produced, on average, 67 percent of the world's almonds; ranging as high as 75 percent in 1996. The California almond industry has 6,000 growers with production in three distinct regions (Northern Sacramento Valley, Central San Joaquin Valley and Southern San Joaquin Valley).

Table 14A. Total almond acres planted, reported pounds of all AIs, acres treated, and prices for almonds each year from 1998 to 2002.

Table 14B. Percent difference from previous year for almond acres planted, reported pounds of all AIs, acres treated, and prices for almonds from 1998 to 2002.

Figure 12. Acres treated in almond by all active ingredients in the major types of pesticides from 1993 to 2002.

The major insecticides by acres treated in almonds in 2002 were petroleum oil, avermectin, propargite, permethrin, and esfenvalerate; the major fungicides were cyprodinil, iprodione, copper hydroxide, azoxystrobin, and ziram; and the major herbicides were glyphosate, oxyfluorfen, paraquat dichloride, simazine, and 2,4-D. The use of most pesticides increased in 2002. The largest increases between 2001 and 2002, of all pesticides in pounds AI, were "petroleum oil, unclassified," mineral oil, 1,3-D, glyphosate, and methyl bromide.

In 2002, pest levels were low in the northern growing region. Wet weather in November-December 2001 in the north helped reduce over-wintering navel orangeworm (NOW) populations by reducing the number of mummies in the trees. This resulted in less 2002 NOW problems and treatments. Weather in the central and southern regions was not exceptionally wet. Generally growers checked for mummies; and, if numbers were high, they used a winter sanitation program to help reduce the over-wintering population.

Other factors play a role in understanding trends in pesticide use. Bearing almond acreage continues to increase resulting in the likelihood of increased applications. Production was also up in 2002, along with the price for almonds. In a good year, growers generally are more inclined to treat with pesticides to protect the crop, thereby increasing the number of applications.

Most of the increase in insecticide use in 2002 was to control San Jose scale, NOW, and mites. Dormant oils showed a significant increase in 2002, establishing a trend of oil treatment alone to control San Jose scale, other scales, and mite eggs. Use of highly toxic organophosphates such as azinphos methyl and methidathion to control peach twig borer continues to decrease. Diazinon use was up slightly in 2002, but still on a decline overall. Monitoring, using egg traps, is the primary means for determining whether to treat for NOW at hull split. A lot of growers reportedly are not comfortable using the traps so they still treat by the calendar, using the traps to determine the optimum time to treat. The use of the reduced-risk pesticide tebufenozide to control NOW increased in 2002.

Herbicide use increased both in pounds applied and acres treated. Oxyfluorfen had the greatest increase by acres treated. However, there was also an increase in contact herbicides such as glyphosate and paraquat dichloride indicating a possible shift away from pre-emergent herbicides. Also, the use of 1,3-D is up significantly continuing a trend away from the use of methyl bromide to control soil pests.

Alfalfa

Alfalfa hay is produced for animal feed. Most counties produce some alfalfa, but the leading producers are Imperial, Kern, Tulare, Merced, and Fresno counties. Alfalfa acres have increased in the state. Production of hay, of which nearly 85 percent is alfalfa hay, surpassed cotton production as the state's highest-valued field crop in 2001. The dairy industry is the biggest market for alfalfa hay production.

Table 15A. Total alfalfa acres harvested, reported pounds of all AIs, acres treated, and prices for alfalfa each year from 1998 to 2002.

Table 15B. Percent difference from previous year for alfalfa acres harvested, reported pounds of all AIs, acres treated, and prices for alfalfa from 1998 to 2002.

Figure 13. Acres treated in alfalfa by all active ingredients in the major types of pesticides from 1993 to 2002.

Trifluralin, the leading herbicide used in each of the last three years, was used primarily for summer grass control, but also in response to dodder. Pounds of AI applied increased by 14 percent compared to 2001, in line with the increase in acres. Diuron use increased 41 percent, most likely to reduce costs and broaden winter weed control when combined with hexazinone, which increased 15%.

Insecticide use in pounds was reduced by 12 percent overall, despite the increase in acreage. Of the major insecticides, chlorpyrifos, methomyl, and endosulfan use decreased 20, 52, and 61 percent, respectively. Chlorpyrifos is used primarily for Egyptian alfalfa weevil, and the pyrethroids (such as lambda-cyhalothrin, cyfluthrin, and permethrin) have replaced chlorpyrifos during the winter and early spring. The decrease in methomyl is likely attributed to the rapid acceptance of indoxacarb for late season armyworm control. Indoxacarb, a new insecticide for lepidopteran pests and leafhoppers, became the tenth most popular AI in a single year, going from no use in 2001 to 7,211 pounds AI in 2002. It was the seventh most popular insecticide in terms of acres treated (96,735 acres). Malathion (16 percent), dimethoate (11 percent), and carbofuran (6 percent) use increased moderately.

Fungicide use in alfalfa was insignificant and mirrored the use in 2001.

Rice

The 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, Butte, Sutter, and Glenn. Approximately 600,000 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 16A. Total rice acres planted, reported pounds of all AIs, acres treated, and prices for rice each year from 1998 to 2002.

Table 16B. Percent difference from previous year for rice acres planted, reported pounds of all AIs, acres treated, and prices for rice from 1998 to 2002.

Figure 14. Acres treated in rice by all active ingredients in the major types of pesticides from 1993 to 2002.

The major insecticides by acres treated in rice in 2002 were lambda-cyhalothrin, diflubenzuron, limonene, and carbaryl; the major herbicides were propanil, triclopyr, thiobencarb, molinate, and bispyribac-sodium; and the major fungicides were copper sulfate (pentahydrate) and azoxystrobin. Pesticides with large increases in use include bispyribac-sodium, azoxystrobin, thiobencarb, triclopyr, lambda-cyhalothrin, and molinate. Those with large decreases in use include 2,4-D, bensulfuron-methyl, MCPA, copper sulfate (pentahydrate), and diflubenzuron.

The increase in rice acreage was a big factor in most cases where pesticide use increased. In 2002, there were no major shifts in pest pressure. Herbicides accounted for the largest portion of rice pesticides. Propanil and triclopyr usage remained stable; the moderate increases were due to the increase in rice acreage. Besides acreage, other reasons for increased herbicide use include pest resistance, increased grower confidence with use of new herbicides on the market, and the fit of older herbicides with the new herbicides (increased use of those with the best fit). Bispyribac-sodium is a new herbicide, providing excellent watergrass and rice field bulrush control and effective control of California arrowhead. Carfentrazone-ethyl use has increased due partly to the decreased use of bensulfuron-methyl and MCPA, and better development of the compound with ground applications into the water to avoid drift. MCPA and 2,4-D use continue to decline as all registrations (except one 2,4-D label) were cancelled a few years ago. Growers use only material on hand when needed for broadleaf weed control. Growers are also substituting other broadleaf herbicides for MCPA and 2,4-D such as triclopyr, propanil, and carfentrazone-ethyl. Bensulfuron has a declining market share due to widespread pest resistance. Fenoxyprop use continues to decline because of problems with uneven results and frequent rice damage. Favorable weather conditions contributed to the decrease in the algae problem and the use of copper sulfate from 2001 to 2002. The use of some herbicides such as bensulfuron-methyl continued to decline due to widespread pest resistance.

The large increase in use of the fungicide azoxystrobin was due more to an aggressive marketing campaign than a change in status of target pests. Use of the insecticides lambda-cyhalothrin and diflubenzuron replaced carbofuran for rice water weevil (RWW) control in 2000 after the rice production season. Increased grower experience and confidence with the use of these new insecticides contributed to the continued increases in use. Lambda-cyhalothrin is most popular among growers for RWW control. The diversity of labeled uses for lambda-cyhalothrin (RWW, midge, and armyworm) may also have contributed to its increased use.

Tomatoes (Processing)

Virtually all of the 296,000 acres of processing tomatoes grown in 2002 were located in the Sacramento Valley (29 percent) or San Joaquin Valley (69 percent). Fresno County had the largest acreage (106,900 acres), followed by Yolo County (41,600 acres) and San Joaquin County (32,600 acres). Most of the acreage increase from 2001 to 2002 (nearly 30,000 acres) occurred in the San Joaquin Valley region; acreage in the Sacramento Valley remained static.

Table 17A. Total processing tomato acres planted, reported pounds of all AIs, acres treated, and prices for processing tomato each year from 1998 to 2002.

*From Chuck Rivera, California Tomato Research Institute, Inc, taken from a recent section 18 application for Dual® use in tomatoes.

Table 17B. Percent difference from previous year for processing tomato acres planted, reported pounds of all AIs, acres treated, and prices for processing tomato from 1998 to 2002.

Figure 15. Acres treated in processing tomatoes by all active ingredients in the major types of pesticides from 1993 to 2002

Total pounds of pesticide active ingredient used on processing tomatoes in 2002 increased by almost 3 million pounds. However, pesticide use in 2002 was nearly identical to use in 2000. The low use in 2001 was due to favorable weather for the crop.
A major factor in the increased pesticide use was the increase in acres planted. There were no major pest outbreaks, and transplant acres remained similar to 2001. Growers were concerned about the costs and availability of hand labor, reflected in a general increase in herbicide use (including the use of metam-sodium as an herbicide treatment). Most preplant herbicide use increased in 2002. A shortage of pebulate, corrected in 2002, may account for the 78 percent increase in its use by pounds of AI. Trifluralin, metolochlor, and metribuzin all increased, 43, 30, and 54 percent, respectively.

Sulfur and metam-sodium made up over 90 percent of the total pounds of AIs applied to tomatoes in 2002, similar to the trend in 2001. Sulfur is used for russet mite and powdery mildew, annual pests throughout California. Growers replaced some metam-sodium use with rimsulfuron, doubling its use in 2002. In terms of acres treated, rimsulfuron, an herbicide used at low application rates, was applied on more acres than all herbicides other than trifluralin (122,427 acres). A drop in price was the reason for the shift.

Early season weather in March and April did not favor bacterial speck and other early season diseases; therefore, the use of copper hydroxide, mancozeb, and maneb decreased. A September heat wave coupled with a larger-than-expected crop resulted in the application of late season fungicides and sun-block (kaolin) in an attempt to carry the crop through to harvest. Use of kaolin, technically classified as a fungicide, increased to 67,317 lbs in 2002 from only 5,795 pounds in 2001, most applied in July. Use of chlorothalonil increased 34 percent, mostly applied in August for late-season disease control, again an attempt to carry the crop further into the fall to accommodate harvest.

Insecticide use decreased 12 percent from 2001 to 2002. Imidacloprid, an insecticide used at a low rate, increased during April and May and again slightly in July. It is used for potato aphid control. Acres treated with imidacloprid increased from 75 acres to 4,384 acres, comparing April 2001 to April 2002. Replacement of dimethoate with imidacloprid resulted in decreased use of dimethoate.

Head (Iceberg) 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 (Ventura and Santa Barbara counties); the San Joaquin Valley (Fresno, Kings, and Kern counties); and the southern deserts (Imperial and Riverside counties). In 2002, 55 percent of all California head lettuce was planted in the central coastal area, 16 percent in the southern coastal area, 17 percent in the San Joaquin Valley, and 12 percent in the southern deserts. California produces approximately 72 percent of the head lettuce grown in the United States annually.

Table 18A. Total head lettuce acres harvested, reported pounds of all AIs, acres treated, and prices for head lettuce each year from 1998 to 2002.

Table 18B. Percent difference from previous year for head lettuce acres harvested, reported pounds of all AIs, acres treated, and prices for head lettuce from 1998 to 2002.

Figure 16. Acres treated in head lettuce by all active ingredients in the major types of pesticides from 1993 to 2002.

During 2002, the top insecticides used (by acres treated) were permethrin, diazinon, spinosad, acephate, and imidacloprid. The main fungicides used were maneb, iprodione, fosetyl-al, acibenzolar-S-methyl, and vinclozolin. Three herbicides dominated ? propyzamide (pronamide), bensulide, and benefin. Four fumigants?metam-sodium, 1,3-D, chloropicrin, and methyl bromide?were used.

There was less insecticide, fungicide, and herbicide use during 2002 than in 2001, and a 6 percent reduction from 2001 to 2002 in acres of head lettuce harvested. However, fumigant use increased.

Permethrin and spinosad are used to manage larvae of beet armyworm and cabbage looper. Use of permethrin dropped in 2002, possibly due to less worm pressure throughout California, and the increased use of many reduced-risk insecticides such as spinosad and emamectin. In the central coastal area, insecticides other than permethrin such as avermectin were used to manage leafminers. Use of spinosad also increased in 2002, possibly due to concern about thrips damage. Thrips have become important pests in coastal and desert regions of California. Diazinon is mostly used as a preplant treatment to manage soil pests and occasionally thrips. Use of diazinon increased in the coastal areas due to pressure from springtails and symphylans and in the southern deserts due to thrips. Increased use of lambda-cyhalothrin in the southern deserts may have also targeted thrips.

In 2002, maneb was the dominant fungicide used in head lettuce production, primarily to control downy mildew and prevent anthracnose. There was a reduction in use of fosetyl-al, an alternative to maneb for controlling downy mildew. Iprodione, used to treat lettuce drop, was the second most widely used fungicide for head lettuce; unlike vinclozolin and dicloran, which are also used for lettuce drop management, its use in 2002 was higher than that used in 2001. Use of acibenzolar-S-methyl, first registered for lettuce in 2001, increased seven-fold in one year, elevating it to fourth place for number of acres treated. This new reduced-risk fungicide stimulates plants to resist the pathogen that causes downy mildew. Use of another new biofungicide, QST 713 strain of dried Bacillus subtilis, increased five-fold from 2001 to 2002. First registered for use on lettuce in 2000, B. subtilis manages bacterial leaf spot.

Use of propyzamide (pronamide), applied as a postplant-pre-emergent herbicide, decreased from 2001 to 2002, but as consistent with its use for the past ten years, was applied to many more acres than the pre-emergent bensulide, which targets small-seeded annual grasses and is not as efficacious as propyzamide in the coastal areas. Benefin is used as a pre-plant herbicide, especially in the San Joaquin Valley and the southern deserts.

Nematodes are rarely economic pests of head lettuce, so soil is primarily fumigated to control soil-borne diseases. In 2002 the number of acres treated with methyl bromide fell to half the number treated in 2001, while acres treated with1,3-D jumped nearly ten-fold. 1,3-D combined with chloropicrin reduces soil populations of Verticillium wilt. Although primarily used as a fumigant to control soil-borne diseases, metam-sodium can also be used to control weeds, if somewhat unreliably. In 2002, five times more acres were treated with this fumigant and preplant herbicide than in 2001.

Oranges

Eighty-six percent of California oranges are grown in the San Joaquin Valley. 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).

Table 19A. Total orange bearing acres, reported pounds of all AIs, acres treated, and prices for oranges each year from 1998 to 2002.

Table 19B. Percent difference from previous year for orange bearing acres, reported pounds of all AIs, acres treated, and prices for oranges from 1998 to 2002.

Figure 17. Acres treated in oranges by all active ingredients in the major types of pesticides from 1993 to 2002.

The major insecticides by acres treated in oranges in 2002 were petroleum oil, spinosad, chlorpyrifos, cyfluthrin, and pyriproxyfen; the major fungicides were copper hydroxide and copper sulfate (basic); and the major herbicides were glyphosate, diuron, and simazine. The use of pesticides did not increase much above the 2001 level (by acres treated), and since 1993 use has declined overall. However, some specific pesticides did show increases from 2001 to 2002: copper sulfate, spinosad, copper hydroxide, cyfluthrin, simazine, diuron, and glyphosate.

The major insect pests in citrus are citrus thrips, scale, orangeworms, and katydids. A new pest in the Coachella Valley, the citrus leafminer, is under quarantine. The Mexican Fruit Fly infestation impacted fruit prices from Southern Riverside County and Northern San Diego County. Growers are required to spray for glassy-winged sharpshooters (GWSS) in most of the citrus-growing regions. According to the National Oceanic and Atmospheric Administration, the citrus-growing regions of California had a dry year with the interior region receiving only 25 percent of normal rainfall. Temperatures in the eastern part of the state were 3 percent above normal. The higher temperatures caused California red scale populations to increase.

Petroleum oil is a broad-spectrum insecticide for aphids, mites, and scales; chlorpyrifos is a broad-spectrum insecticide for insects; cyfluthrin is used for citrus thrips, katydids, and worms; spinosad is used for citrus thrips, orangeworms, and katydids; pyriproxyfen is used to control red scale; and imidacloprid is used to manage GWSS and leafminer. Pyriproxyfen, an insect growth regulator, is not working as well as it did when first introduced in 1998, suggesting that pest resistance may be developing. Growers prefer to use pyriproxyfen for red scale control because it is cheaper, more effective, and has a shorter pre-harvest interval than buprofezin, another insect growth regulator.

The increase in spinosad use was probably due to the increased number of bearing acres. In addition, citrus thrips are developing resistance to pyrethroids; therefore, growers use cyfluthrin in a tank mix with spinosad, which may also explain the increase in use for cyfluthrin. The mandated spray program for GWSS is disrupting the reduced-risk approach that is in place in the interior region. Kern County also reports that the effort to control GWSS is increasing the use of imidacloprid. Growers prefer using a systemic pesticide like imidacloprid that does not impact beneficial insects. Japan lowered the acceptable maximum residue limits for chlorpyrifos, which significantly impacted citrus by preventing use of the product, a valuable IPM tool for citrus.

The fungicides copper hydroxide and copper sulfate are used to prevent Phytophthora gummosis, Phytophthora root rot, and fruit diseases such as brown rot and Septoria spot. When acreage begins bearing fruit, growers use one or two applications of copper spray to protect the fruit. Increases in copper sulfate and copper hydroxide were probably due to the increased number of acres coming into production.

The herbicide glyphosate is used to control weeds post-emergence; diuron and simazine are used for pre-emergent weed control. Since growers use herbicides to prepare the ground prior to planting, glyphosate, simazine and diuron increases are most likely due to the increase in acres planted.

Peaches/Nectarines

California ranks first in the U.S. in the production of peaches and nectarines, producing 71 percent of the peaches in the U.S. and 99 percent of the nectarines. California produces 100 percent of the U.S. processed peaches and 49 percent of the U.S. fresh market peaches. Clingstone peaches comprise approximately 70 percent of the total peach crop in California and are exclusively utilized for processing, which includes canning (including baby food), juice, and frozen. The California fresh shipping freestone peach production represents 30 percent of the annual tonnage. Clingstone peach acreage increased slightly in 2002 over 2001, while freestone peach and nectarine acreage remained unchanged. Pest management issues for peaches and nectarines are nearly identical so these crops are discussed together.

Table 20A. Total peach/nectarine bearing acres, reported pounds of all AIs, acres treated, and prices for peaches/nectarines each year from 1998 to 2002.

Table 20B. Percent difference from previous year for peach/nectarine bearing acres, reported pounds of all AIs, acres treated, and prices for peaches/nectarines from 1998 to 2002.

Figure 18. Acres treated in peaches and nectarines by all active ingredients in the major types of pesticides from 1993 to 2002.

The major insecticides by acres treated in peaches/nectarines in 2002 were esfenvalerate, petroleum oil unclassified, phosmet, mineral oil, and the pheromones E-8-dodecenyl acetate, Z-8-dodecenyl acetate, and Z-8-dodecenol; the major fungicides were sulfur, copper hydroxide, iprodione, propiconazole, and ziram; and the major herbicides were glyphosate, oxyfluorfen, paraquat dichloride, simazine, and norflurazon. The use of many pesticides increased in 2002. The largest increases (pounds AI) were mineral (horticultural) oil, 1,3-D, sulfur, copper sulfate (basic), copper oxide, and petroleum oil unclassified. Small increases were reported for chlorpyrifos, carbaryl, and methomyl. Overall, use of diazinon continues to decline. In addition, use of propargite was also down in 2002 along with large decreases in copper hydroxide, ziram, and copper sulfate (pentahydrate).

Oriental fruit moth (OFM) was a particular problem in 2002. The season started with a larger over-wintering population of OFM that required supplemental treatments in addition to a mating disruption program. Windy periods during May and June in the Sacramento Valley may have negatively affected pheromone-mating disruption programs. Controlling San Jose scale (SJS) continues to be a primary concern for freestone growers in the San Joaquin Valley. Mites were not particularly a problem; some growers had them, others did not. Katydids continue to be a secondary pest of concern in the south. As growers continue to move away from broad-spectrum pesticides, the incidence of fruit damage by katydids is more prevalent.

Most of the increase in insecticide use in 2002 was to control SJS and OFM. Used in-season, mineral (horticultural) oil was effective in controlling scale crawlers and mites. Increases in the use of phosmet, carbaryl, and methomyl on freestone varieties, was probably due to late season treatments for OFM. Many freestone growers used pheromone mating-disruption for OFM early in the season. Some growers reportedly were not pleased with the results and did not do a mid-season second hanging of pheromone dispensers (due to the labor cost to hang). Many clingstone growers reportedly used sprayable pheromones in their conventional spray (i.e., pyrethroids to control peach twig borer [PTB]). While this practice may have increased pesticide use, it also appeared that the treatments might have been more efficacious. Overall, PTB treatments using Bt and spinosad were up in 2002. As in 2001, growers continue the trend of using 1,3-D instead of methyl bromide to kill soil pests during replanting operations.

Walnuts

California produces 99% of the walnuts grown in the United States and accounts for 38 percent of the world's production. California exports more than 40 percent of its walnut crop. Thirty-five percent of the crop is marketed in shell. Bearing walnut acreage in California increased from 196,000 in 2001 to approximately 200,000 in 2002. Yield per acre in 2002 was 1.41 tons compared to 1.56 tons in 2001. As a result, estimated total production was also down in 2002, compared to 2001.

Table 21A. Total walnut bearing acres, reported pounds of all AIs, acres treated, and prices for walnuts each year from 1998 to 2002.

Table 21B. Percent difference from previous year for walnut bearing acres, reported pounds of all AIs, acres treated, and prices for walnuts from 1998 to 2002.

Figure 19. Acres treated in walnuts by all active ingredients in the major types of pesticides from 1993 to 2002.

The major insecticides by acres treated in walnuts in 2002 were chlorpyrifos, propargite, methyl parathion, esfenvalerate, and tebufenozide; the major fungicides were copper hydroxide, maneb, copper oxide, and copper ammonium complex; and the major herbicides were glyphosate, oxyfluorfen, simazine, paraquat dichloride, and diuron. The use of most pesticides increased in 2002. The largest increases (pounds AI) were in copper hydroxide, maneb, 1,3-D, methyl bromide, and glyphosate.

Part of the increased use of pesticides in 2002 was due to an increase in bearing acreage statewide. Most of the increase in insecticide use was to control codling moth (CM). Overall, insecticide use in 2002 declined. Populations of CM were low to moderate in the first half of the season. In some areas, late flights were detected, indicating a need to treat. This extended the season by requiring additional treatments. Chlorpyrifos was the primary pesticide used for CM control along with esfenvalerate. Chlorpyrifos use was about the same in 2002 as 2001, and esfenvalerate use decreased; by far the largest increase was hydrolyzed corn product. In addition, the reduced-risk pesticide tebufenozide also showed a sharp increase in 2002. Walnut husk fly was a problem later in the season and required treatment with malathion. Walnut aphid was a secondary pest in some orchards, which resulted in the need for additional treatments of chlorpyrifos and naled.

Other factors played a role in the increased use of pesticides in walnuts. Using a computer index, conditions for development of walnut blight were observed later in the season than normal. This resulted in additional fungicide treatments in May, which accounts for the increase in fungicides applied. The use of glyphosate as a contact herbicide increased in 2002. One explanation may be a practice that involves treating with glyphosate between the tree rows to knock down resident vegetation. This is done to facilitate harvest particularly if a late harvest is anticipated. Use of 1,3-D was up significantly in 2002, since it is used as a replacement for methyl bromide to control soil pests prior to replanting and when planting new orchards. However, methyl bromide use also increased from 2001 to 2002.

Leaf Lettuce

Leaf 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 (Ventura and Santa Barbara counties; the San Joaquin Valley (Fresno, Kings, and Kern counties); and the southern deserts (Imperial and Riverside counties). In 2002, 68 percent of all California leaf lettuce was planted in the central coastal areas, 13 percent in the southern coastal areas, 6 percent in the San Joaquin Valley, and 13 percent in the southern deserts. California produces approximately 81 percent of the leaf lettuce grown in the United States. Romaine dominates the leaf lettuce market in California with approximately 63 percent of production followed by green leaf, 23 percent; red leaf, 10 percent; and butterhead, 4 percent.

Table 22A. Total leaf lettuce acres harvested, reported pounds of all AIs, acres treated, and prices for leaf lettuce each year from 1998 to 2002.

Table 22B. Percent difference from previous year for leaf lettuce acres harvested, reported pounds of all AIs, acres treated, and prices for leaf lettuce from 1998 to 2002.

Figure 20. Acres treated in leaf lettuce by all active ingredients in the major types of pesticides from 1993 to 2002.

During 2002, the top insecticides used (by acres treated) were imidacloprid, permethrin, diazinon, spinosad, and lambda-cyhalothrin. The main fungicides used were maneb, fosetyl-al, iprodione, acibenzolar-S-methyl, and dicloran. Propyzamide was the main herbicide applied, followed by bensulide and benefin. Metam-sodium was used almost to the exclusion of the two other fumigants, 1,3-D and chloropicrin. No methyl bromide was applied during 2002.

There was more fungicide and herbicide used during 2002 than in 2001, and no change in acres of leaf lettuce harvested.

Imidacloprid, generally applied to control aphids in coastal areas and whiteflies in the southern deserts, was used on more acres than any other insecticide. In the coastal areas a large portion of the romaine crop is processed as salad mix, and aphids are unacceptable to salad packers. In the southern deserts, one application of imidacloprid at planting will usually control whitefly, and will carry over for aphid control in the winter and spring. Permethrin is used to manage leafminers, thrips, and larvae of beet armyworm and cabbage looper. Use of permethrin increased in 2002 in all areas except for the central coast, where the use of many reduced-risk insecticides such as spinosad and indoxacarb are gaining favor. Diazinon is used mostly as a preplant treatment to manage soil pests and occasionally thrips. Use of diazinon increased in the coastal regions due to pressure from springtails and symphylans and in the desert regions due to thrips. Thrips have become important pests in the coastal areas and southern deserts of California. Use of spinosad, which is used to manage lepidopterous larvae (worms) and thrips, increased in 2002 in all lettuce-growing regions except the southern deserts, where there was less worm pressure than in 2001. Increased use of lambda-cyhalothrin in the southern deserts may have also targeted thrips.

In 2002, maneb was the dominant fungicide used in leaf lettuce production, primarily to control downy mildew and prevent anthracnose. There was a reduction in use of fosetyl-al, an alternative to maneb for controlling downy mildew. Iprodione, used to treat lettuce drop, was the third most widely used fungicide for leaf lettuce. Dicloran, also used for lettuce drop, decreased in use throughout the state to fifth place. Dicloran was not used at all in the southern deserts, but was popular in the southern coastal area, especially Ventura County. Use of acibenzolar-S-methyl, first registered for lettuce in 2001, increased four-fold in one year, elevating it to fourth place for number of acres treated. This new reduced-risk fungicide stimulates plants to resist the pathogen that causes downy mildew. Use of another new biofungicide, QST 713 strain of dried Bacillus subtilis, more than doubled from 2001 to 2002. First registered for use on lettuce in 2000, B. subtilis manages bacterial leaf spot.

Use of propyzamide (pronamide), applied as a postplant-pre-emergent herbicide, increased from 2001 to 2002 but, consistent with its use for the past ten years, was applied to many more acres than bensulide, another pre-emergent, which is not as efficacious as propyzamide in the coastal areas. Use of bensulide increased slightly from 2001 to 2002, primarily due to its widespread use in the southern deserts where almost as much was applied as propyzamide. (The statewide ratio of propyzamide to bensulide was four to one.) Benefin is used as a pre-plant herbicide, especially in the San Joaquin Valley and desert areas. Its use decreased overall, except in the central coastal area, where it was used to treat more acres in 2002 than in 2001.

During 2002, fumigants were used on few acres. Nematodes are rarely economic pests of leaf lettuce, so soil is primarily fumigated to control soil-borne diseases. From 2001 to 2002, the number of acres treated with metam-sodium doubled. Although primarily used as a soil fumigant to control soil-borne diseases, metam-sodium can also be used as a preplant herbicide, although results are somewhat unpredictable. No methyl bromide was applied in 2002, probably due to the phaseout of this fumigant in 2005. 1,3-D combined with chloropicrin reduces soil populations of Verticillium wilt. Use of 1,3-D increased only in the southern deserts.

Strawberries

Strawberries are grown for mostly fresh market. Depending on market prices, some are processed. California strawberry production occurs primarily along the central and southern coast, with a small but significant production occurring in the central valley.

Table 23A. Total strawberry acres harvested, reported pounds of all AIs, acres treated, and prices for strawberries each year from 1998 to 2002.

Table 23B. Percent difference from previous year for strawberry acres harvested, reported pounds of all AIs, acres treated, and prices for strawberries from 1998 to 2002.

Figure 21. Acres treated in strawberries by all active ingredients in the major types of pesticides from 1993 to 2002.

Strawberry production relies on several fumigants (e.g., methyl bromide, chloropicrin, 1,3-dichloropropene, and metam-sodium) that are generally used at high rates. Fumigants are applied at high rates, in part, because they treat a volume of space rather than a surface area such as the leaves and stems of plants. Thus, the pounds applied are large even though the number of applications or number of acres treated may be relatively small. Fumigants accounted for about 89 percent of all pesticide active ingredients by pounds applied in strawberries. Methyl bromide use decreased 2 percent (from 3,777,550 pounds in 2001 to 3,706,589 pounds in 2002). This decrease in methyl bromide use is likely due to expanded restrictions that DPR placed on field applications in the last few years and the federally mandated phaseout which has significantly increased the price of methyl bromide. Growers are replacing methyl bromide with 1,3-D, and metam-sodium. Use of metam-sodium and 1,3-D more than doubled by both acres treated and pounds applied. Chloropicrin use in pounds decreased by 3 percent from 2001 to 2002. The use of a methyl bromide formulation that contained less chloropicrin likely explains this decrease.

Total acres treated and pounds applied increased from 2001 to 2002 for the major fungicides captan, sulfur, myclobutanil, and fenhexamid, likely due to favorable weather for disease development, a longer growing season, and increased acreage in 2002. Iprodione, benomyl, and thiram use decreased significantly from 2001 to 2002. The use of iprodione and benomyl are being phased out for strawberry production. Thiram was likely replaced by fenhexamid and the newly registered azoxystrobin whose uses increased by 6,879 and 4,459 pounds, respectively.

Carrots

California ranks among the top in the U.S. in the production of carrots. Carrots are grown for fresh market and processing. California has four main production regions for carrots: the San Joaquin Valley (Kern County), with significant production in Cuyama Valley (San Luis Obispo County); the low desert (Imperial Valley and Riverside counties); the high desert (Los Angeles County); and the central coast (Monterey County).

Table 24A. Total carrot acres harvested, reported pounds of all AIs, acres treated, and prices for carrots each year from 1998 to 2002.

Table 24B. Percent difference from previous year for carrot acres harvested, reported pounds of all AIs, acres treated, and prices for carrots from 1998 to 2002.

Figure 22. Acres treated in carrots by all active ingredients in the major types of pesticides from 1993 to 2002.

Most of the pesticides used, as measured by acres treated, were fungicides. Use of all pesticide types, except for insecticides, increased. The major foliar applied fungicides by acres treated in carrots in 2002 were mefenoxam, iprodione, sulfur, and chlorothalonil. The use of these fungicides increased by at least 20 percent. This increase was most likely due to weather favorable for development of powdery mildew and Alternaria leaf blight, the most damaging foliar disease of carrots. Metalaxyl use, the mostly widely used fungicide from 1994 to 1996, has been phased out; its use decreased to nearly zero in 2002. To control cavity spot, the most troublesome root disease in carrots, growers use mefenoxam, which has replaced metalaxyl. Therefore, mefenoxam use in pounds increased by 13 percent in 2002.

Carrot production relies on several fumigants (1,3-D, chloropicrin, and metam sodium) that generally are used at high rates to control soil borne pests and weeds. Methyl bromide is no longer used on carrot acreage. In 2002, fumigants accounted for about 85 percent of the total pounds of pesticide AIs applied to carrots. Acres treated and pounds of 1,3-D used increased by more than 140 percent in 2002. Chloropicrin use also increased (31 percent more acres were treated than in 2001); however, chloropicrin is not used by itself in carrot production. It is contained in a formulation of 1,3-D; therefore, the increase in chloropicrin use is likely due to the increased use of 1,3-D. The use of metam sodium also increased.

Herbicide use increased while acres planted decreased, implying an increase in use per acre planted. The primary increase was in linuron, used to control annual broadleaf weeds and yellow nutsedge. Trifluralin use also increased. It is used to control annual grasses and some small-seeded broadleaf weeds.

Sources of Information

California Agricultural Statistics Service (CASS). January 31, 2003. California Processing Tomato Report, Sacramento, CA

CASS. 2003. California Field Crop Review: 24(1).

CASS. 2003. California Field Crop Review: 24(2).

CASS. 2003. California Fruit and Nut Review: 23(3).

CASS. 2003. California Vegetable Review: 24(1).

California Commodity Associations and Commissions

California Department of Food and Agriculture. 2002. Resource Directory California Agriculture: A Tradition in Innovation. Sacramento, CA. http://www.cdfa.ca.gov/card/pdfs/Directory.pdf

Cotton Insect Losses 2002. http://www.entomology.msstate.edu/resources/tips/cotton-losses/data/2002/2002loss.htm.

County Agricultural Commissioners

Goodell, P. 2002. Sticky Cotton Contamination. California Cotton Review, vol. 64.

Goodell, P., Godfrey, L., Grafton-Cardwell, B., Toscano, N., Wright, S. Insecticide and Miticide Resistance Management in San Joaquin Valley Cotton for 2001, UC DANR Publication 8033.

Growers

National Agricultural Statistics Service (NASS). 1999. Agricultural Prices 1998 Summary. USDA. Pr 1-3 (99)a.

NASS. 2002. Agricultural Prices 1999 Summary. USDA. Pr 1-3 (00)a.

NASS. 2001. Agricultural Prices 2000 Summary. USDA. Pr 1-3 (01)a.

NASS. 2002. Agricultural Prices 2001 Summary. USDA. Pr 1-3 (02)a.

NASS. 2003. Agricultural Prices 2002 Summary. USDA. Pr 1-3(03)a.

NASS. 2003. Crop Values 2002 Summary. USDA. Pr 2 (03).

NASS. 2003. Farm Production Expenditures 2002 Summary. United State Department of Agriculture (USDA). Sp Sy 5(03).

National Oceanic and Atmospheric Administration. 2003. Climate. http://www.noaa.gov/climate.html

Pest Control Advisors

Pest Management Strategic Plan for California and Arizona Lettuce Production 2003. Summary of a workshop held on June 18, 2002. USDA, Salinas, CA.

Pest Management Strategic Plan in California Cotton Production. 2002. Summary of a workshop held on November 15, 2001 UC Kearney Ag Center.

Ross, Karen. 1999. California Winegrape Pest Management Alliance Evaluation. Submitted to the Department of Pesticide Regulation by the California Association of Wingegrape Growers.

Snyder, Jack. Fall 2001 and 2002. The California Tomato Grower report. Tomato Growers' Association.

United States Department of Agriculture (USDA). 1999. Crop Profile for Almonds in California.
(USDA crop profiles can be found at http://pestdata.ncsu.edu/cropprofiles/pmcropprofiles.cfm?usdaregion=Western)

USDA. 2000. Crop Profile for Carrots in California.

USDA. 2002. Crop Profile for Cotton in California.

USDA. 1999. Crop Profile for Grapes (Raisin) in California.

USDA. 1999. Crop Profile for Grapes (Table) in California.

USDA. 2002. Crop Profile for Grapes (Wine) in California.

USDA. 2001. Crop Profile for Iceberg Lettuce in California.

USDA. 2001. Crop Profile for Leaf Lettuce in California.

USDA. 1999. Crop Profile for Peaches in California.

USDA. 1998. Crop Profile for Rice in California.

USDA. 1999. Crop Profile for Strawberries in California.

USDA. 1998. Crop Profile for Walnuts in California.

University of California (UC). 1990. Integrated Pest Management for Tomatoes. 3rd edition. Statewide Integrated Pest Management Project, Division of Agriculture and Natural Resources, UC Davis.

UC Cooperative Extension Area IPM Advisors

UC Cooperative Extension Farm Advisors

UC Cooperative Extension Specialists

UC Researchers

Weather station data from California Irrigation Management Information System (CIMIS), California Department of Water Resources. http://www.cimis.water.ca.gov/cimis/data.jsp

Return to top.

Back to 2002 Pesticide Use Reporting (PUR) Menu.