Washington State Tree Fruit IPM Project
Many major pear pests in Washington state are no longer easily controlled by the pesticides growers use. At the same time, regulators are taking a closer look at pesticides used in pear production because so many infants and children eat them. In 1997, American Farmland Trust, managing funds from the Pew Charitable Trusts and EPA, joined forces with the Center for Agricultural Partnerships to help pear growers reduce the use of pesticides, lower risks to more acceptable levels and improve the environment in the Pacific Northwest. The multi-year project brought together Del Monte Foods, Snokist Growers, the Washington State Horticultural Association, pest control advisors, Washington State University Cooperative Extension, chemical suppliers and the USDA Agricultural Research Service to help growers implement a more biologically intensive integrated pest management system in the Yakima Valley. The key tactic was the use of insect pheromones for mating disruption to reduce insecticide treatments to control codling moth and thereby increase the populations of beneficial insects to help control pear psylla. The project focused on educating and training growers, increasing the skills and numbers of consultants and developing new information-gathering methods.
By the end of the project, 3,500 acres (191 orchards) were enrolled and had switched to mating disruption tactics. Cost savings for growers averaged $22 per acre with effective control, quality and yield and a reduction of more than 30 percent in organophosphate use. The total acreage enrolled in the project fell short of the original 4,500 acre benchmark, despite concerted efforts by partners and the willingness of Snokist and Del Monte to buy fruit from participating growers regardless of insect damage. This was partly because the average size orchard in the Yakima Valley was less than 10 acres, the minimum recommended for using codling moth mating disruption. The other problems were caused by an economic downturn in the apple and pear market during the project period and the lingering suspicion on the part of growers that IPM might increase the risk of pest damage. A survey of the valley in December 2000 showed the use of codling moth mating disruption increased by 486 percent in three years, 91 percent of the growers were aware of the project and half of those were influenced by the project in their decisions regarding mating disruption use in their orchards. The project also produced economic analyses (Statistical, Partial Budgeting and Net Present Value analyses developed by Jeff Connor, Oregon State University); an Orchard Pest Monitoring Guide for Pears; an IPM manual; a curriculum for the training of field scouts now being offered by local community colleges as part of their associate's programs; and a similar IPM management effort on winter pears in North Central Washington, supported by the Center for Agricultural Partnerships and EPA, that extends the approach to the fresh pear industry. The cooperators recommend expanding the duration of these types of private-public partnerships to five years.