2012 Annual Report
1a.Objectives (from AD-416):
Improve fumigation efficacy with alternatives to methyl bromide for almond orchard replanting using low permeability tarps.
1b.Approach (from AD-416):
Two field trials will be conducted to collect soil fumigant (1,3-D, chloropicrin and methyl iodide) and pest control (e.g., nematode, pathogen, and weed) data under low permeability tarps such as TIF. Fields with naturally occurring nematode and pathogen populations will be selected for fumigation. Treatments will include: control (no fumigation), full rate (maximum allowed) in bare soil, under standard tarp, and TIF tarp, and reduced rates (2/3 and 1/2 of full rate) under TIF. Soil-gas concentrations will be monitored at pest sampling locations and depths. Correlation between fumigant dosage and pest control, and treatment effects will be statistically analyzed. Tarp permeability will be measured before and after installation. Fumigant change in the air under tarp will be monitored to estimate the proper time for the safe removal of TIF tarps to minimize exposure.
This project supports objective 3 of the parent project. The almond industry in California depends on soil fumigation for control of soil-borne pests (nematodes, pathogens, weeds) during replanting as well as during production of pest and pathogen-free nursery stock. Both fumigant emission reduction and improved efficacy are important in the success of soil fumigation and maintaining fumigant availability. The objective of this project is to demonstrate that using totally impermeable film (TIF) will improve efficacy and can reduce fumigant rates in soil fumigation for orchard replanting. This agreement is to fulfill tasks under Project 5302-13220-004-27R in collaboration with University of California, Davis (UCD). In addition to assist in field trial planning, UCD cooperators will conduct nematode and weed efficacy investigations, collecting samples before and after field trials, and correlate pest control data with soil fumigant data. The cooperators will also conduct project extension activities. This contract between ARS and UCD was executed on July 23, 2012. Personnel hiring is in process. A field trial in an almond replanting field has been initiated.