2011 Annual Report
1a.Objectives (from AD-416)
To develop efficient and cost-effective field management practices to minimize emissions of methyl bromide alternative fumigants from pre-plant soil fumigation while achieving effective pest control.
1b.Approach (from AD-416)
Field management methods that have potential to reduce fumigant emissions and improve efficacy will be tested. Methods including fumigant application (new shank design, and drip. vs. shank application), low permeable tarps, irrigation, and soil amendment with organics as well as combination of these methods will be determined for their effectiveness and feasibility. Field trials will be conducted in air-quality non-attainment areas in California including Ventura County and the San Joaquin Valley. Data on emission rates, total emission losses, distribution of fumigants in soil profile and efficacy on soil pest control will be collected. Monitored data will be summarized to identify good and effective practices that can be adopted in growers’ fields.
This Specific Cooperative Agreement supports Objective 3 of the parent project. A large field trial was carried out from June 4 – June 22, 2011 at Lost Hills, in Kern County, CA. Participating in this trial also included regulatory agency California Deparment of Pesticide Regulation (DPR), industry TriCal, Inc., and private consulting firm Sullivan Environmental. The specific objective of this trial was to determine proper tarp-cutting time for low permeability tarp totally impermeable film (TIF) when used for emission control in soil fumigation. Emission, air under tarp, fumigant distribution in soil profile, and residual fumigants were monitored. Measurements on emissions and fumigant movement in soil at tarp-edge areas were also made. Samples, including air emissions using dynamic flux chambers, soil-gas, and soil samples are being processed in the laboratory. The data will be used directly by DPR and to assist DPR in predicting emission flux and determining tarp-covering time to protect workers and bystanders from exposure risks. The outcome of the project will be the adoption of TIF in soil fumigation with regulatory decisions. The project is monitored by the lead scientist by regular emails, telephone calls and site visits.