OPCA Publications & Reports

Cosmetic pesticide use: quantifying use and its policy implications in California, USA

This paper, published in the International Journal of Agricultural Sustainability, quantifies cosmetic pesticide use in two cases in California: stink bug control in processing tomato and red color and large size in table grape. It also discusses how the current food system that supports high cosmetic standards, and thus demands pesticide usage, can inhibit the adoption of and transition to sustainable agricultural systems.

Economic and pest management evaluation of nitroguanidine-substituted neonicotinoid insecticides: eight major California commodities

After releasing their July 2018 neonicotinoid risk assessment, the Department of Pesticide Regulation (DPR) developed a regulatory proposal to mitigate the effect of four neonicotinoid insecticides on managed pollinators. As part of OPCA’s consultation mandate, the following report, completed 29 July 2020, estimates the economic effects of this proposed regulation on eight major California crops. Statewide annual changes in pest management costs for those crops are estimated at $11-13 million, averaged across acreage and pesticide use for three base years (2015–2017).

Economic and pest management evaluation of nitroguanidine-substituted neonicotinoid insecticides: nine major California commodities

This report was completed 26 August 2019 and was part of an initial consultation with the Department of Pesticide Regulation (DPR) on their July 2018 neonicotinoid risk assessment. The report estimates the economic effects of the theoretical cancellation of uses of four neonicotinoid insecticides that are high risk to bees on nine major California crops. Statewide annual changes in pest management costs for those crops are estimated at approximately $150 to 200 million, averaged across acreage and pesticide use for three base years (2015–2017).

Estimated Cost of the Withdrawal of the Insecticide Chlorpyrifos for Six Major California Crops

This article estimates the economic effects of cancellation on six major California crops. Statewide annual revenue losses are estimated at $11.5 million, averaged across acreage and pesticide use for three base years (2015–2017).

Financial effect of limiting pesticide use near schools for almonds in nine counties depends on soils and weather

In 2018 California Department of Pesticide Regulation enacted a regulation regarding the use of pesticides near public K-12 schools and licensed child day care centers, including a provision that bans specific types of applications, including air-blast and air-assist, during weekday school hours (6 a.m. to 6 p.m.) to provide an additional safety margin for pesticide exposure beyond those provided by other regulations. This paper estimates the financial effect on almond growers in nine counties, accounting for four-fifths of total almond production in 2014. Using a methodology that took into account historical weather and soil hydrologic group data, we estimated average annual losses in the nine counties among almond growers would have been under $0.2 million because the regulation would have affected the number of sprays completed for relatively few acres in relatively few years.

Economic and Pest Management Evaluation of the Withdrawal of Chlorpyrifos: Six Major California Commodities

In this report, CDFA’s Office of Pesticide Consultation & Analysis and UC research scientists jointly analyze the economic and pest management implications resulting from the loss of chlorpyrifos in six major California crops.

Economic value of the herbicide dacthal for brassica and allium crops in California.

This paper, published in University of California's ARE Update, summarizes a report on the economic and pest management significance of the herbicide dacthal in certain California vegetable crops. The main report (below) was submitted to DPR in July 2018 in response to findings of dacthal breakdown products in drinking water wells that triggered a review of dacthal under the Pesticide Contamination Prevention Act.

Economic and pest management evaluation of the herbicide dacthal in California agriculture

This is the full report, submitted to DPR in July 2018, that evaluates the economic and pest management issues associated with the herbicide dacthal.

Proactive biological control: A cost-effective management option for invasive pests.

This outlook pieces explores the idea of proactive biological control programs and potential utility for California. Proactive biological control involves identifying and testing natural enemies of a pest that is likely to get to California before it actually arrives.

Economic and pest management analysis of proposed pesticide regulations. In Managing and analyzing pesticide use data for pest management, environmental monitoring, public health and public policy.

This chapter covers elements economic and pest management analyses using California’s pesticide use report data to provide insight into the impacts of proposed regulations A worked example demonstrations how the economic calculations are done while a case study gives a more in depth look at what goes into analyses.

Biological control in greenhouse and nursery production: Present status and future directions.

The authors explore the present status of seasonal inoculative biological control in greenhouses and in ornamental nursery production and discuss the limitations, advantages, and future directions of this pest management strategy.

Draft regulation regarding pesticide applications near schoolsites: Potential economic effects for agriculture.

This report examines the potential economic effects on farmers of the draft regulation governing the use of pesticides in agricultural production near public K-12 schools and state-licensed child daycare facilities proposed by the California Department of Pesticide Regulation.

Exotic terrestrial macro-invertebrate invaders in California from 1700 to 2015: An analysis of records.

The authors document that 1,686 exotic terrestrial macro-invertebrates from 278 families have developed self-sustaining populations in California, between 1700 and 2015. The rate of successful invasions has increased since 1990. The authors suggest that such invasions will continue to increase and more exotic organisms will establish in California because of increasing trade and tourism coupled with insufficient resources for pest surveillance, detection, and post-incursion management.

Evaluation of spray application methods for navel orangeworm control in almonds.

Gear Up/Throttle Down (GUTD) and Inward Only strategies represent potential alternatives to conventional airblast applications to reduce spray drift. This study evaluates Inward Only and a modified version of GUTD in almonds, the largest US tree crop, at the recommended hull split treatment timing for control of navel orange worm (NOW), an important almond insect pest.

Comparing California agricultural land use datasets: coverage, accuracy, and pitfalls.

There are four major datasets of varying spatial resolution and time coverage that track California's agricultural land use: California Department of Pesticide Regulation's (CDPR) pesticide use report data (PUR), the United States Department of Agriculture (USDA) National Agricultural Statistics Service's (NASS) Cropland Data Layer (CDL), county agricultural commissioner crop reports compiled by NASS, and California Department of Water Resources (DWR) land use survey. For many crop/county/year combinations, the calculated total acreage for these datasets were remarkably different. This paper discusses which dataset should be given more credence, depending on crop and county.

Chloropicrin regulatory proposal report. Economic implications of a statewide chloropicrin ban on California agriculture.

This report evaluates a California Department of Pesticide Regulation proposal to modify buffer zone and tarp requirements for the soil fumigant chloropicrin. The analysis estimates the economic and pest management impact of the proposal.

Chloropicrin use requirements impact strawberry growers unequally.

Buffer zone requirements are by nature spatial and their effects are site-specific, with some fields more impacted than others. Using a set of strawberry fields in Ventura County that were preplant soil fumigated in 2013 as a baseline, the authors examined how much acreage eligible for chloropicrin fumigation would have been lost if either of two buffer zone distance regulations had been in effect.

Classical biological control of invasive legacy crop pests: New technologies offer opportunities to revisit old pest problems in perennial tree crops.

This paper reviews classical biological control programs in light of new biological control tools. It suggests that opportunities exist for revisiting old pest problems and funding research programs using new tools for developing biological control programs for legacy pests could provide permanent suppression of some seemingly intractable pest problems.

Nonfumigant strawberry production working group action plan.

The California strawberry industry has relied on preplant soil fumigation to manage soilborne pests that include diseases, nematodes, and weeds. Strawberry growers have switched to other fumigants during methyl bromide’s phaseout, but these fumigants are under regulatory pressure too. This action report discusses research priorities for developing cost-effective management practices for soilborne strawberry pests in the absence of conventional fumigants.

Biological controls investigated to aid management of olive fruit fly in California.

The widespread and rapid establishment of the olive fruit fly in California required immediate changes in integrated pest management (IPM) programs for olives. After finding that resident natural enemies did not provide adequate control, researchers began a worldwide search for parasitoids, with exploration in the Republic of South Africa, Namibia, India, China and other countries. Parasitoids were shipped to California, and most were studied in quarantine to determine the best species for release. Two parasitoid species Psyttalia lounsburyi and Psyttalia humilis were released throughout the state's olive-growing regions, and researchers are studying their effectiveness.

Propargite Critical use report (Sept. 2015). Economic evaluation of propargite critical uses in almond, corn and walnut.

This report analyzes the economic and pest management significance of the miticide propargite in California almond, corn, and walnut production. Almond and walnut have access to other effective miticides but corn growers could face a 5% increase in miticide costs.

Reactivity of volatile organic compounds under low NOx conditions

This report investigates the potential of implementing a pesticide volatile organic compound (VOC) inventory which takes into account the reactivity of pesticide constituents. Currently, VOC inventory is assessed on a simple mass basis, which does not account for actual ozone producing potential of chemicals. A VOC inventory based on chemical reactivity would allow the Air Resource Board to more efficiently account for contributions from various pesticide products.

Emulsifiable concentrate alternatives analysis

The California Department of Pesticide Regulation (CDPR) proposed regulation for emulsifiable concentrate pesticides because they produce high levels of volatile organic compounds. By analyzing past usage patterns and with general knowledge of field use and product efficacy, UC researchers identified a set of alternatives that growers might use in the absence of emulsifiable concentrate formulated products and calculated the cost of switching to the alternatives. Critical uses with no viable alternatives were also identified.

The Economic Importance of Organophosphates in California Agriculture

This study estimates economic impact to California producers and consumers resulting from a total ban of all OP pesticides. It was an interdisciplinary effort, a combination of entomologists’ expert knowledge of pest control and economic modeling. Results of the economic analysis suggest that the total loss to producers and consumers in California from banning all OP use will be approximately $203 million.