Implementation of an area-wide IPM program for leafroller contaminants in caneberries
This project was funded for 2 years (starting March 1, 2004) to develop an area-wide approach to reducing insecticide use for the caneberry harvest contaminant orange tortrix (OT), Argyrotaenaia fransciana. OT is the key pest driving pre-harvest broad-spectrum insecticide applications (primarily bifenthrin, carbaryl, malathion, and azinphos-methyl) in southwest Washington and western Oregon. OT has a significant hatch coinciding with the beginning of caneberry harvest. Because of their numbers and the inability to completely separate them from the fruit once it has been picked, processors have set a zero tolerance for them. During the 2004 season, trained scouts visited the fields weekly (6 cooperating growers: 3 in Washington, 3 in Oregon; a total of 421 acres), allowing for better timing of spray materials used. Proper sprayer calibration and slowing tractor speed improved application coverage and effectiveness. The traditional program varied by pest pressure but often included multiple applications of organophosphates and pyrethroids along with bacillus thuringiensis. This year, growers incorporated area wide scouting and Spinosad along with reduced applications of the broad-spectrum materials to successfully control the pest species. The one organic grower successfully used scouting and two well timed applications of Spinosad to gain control. All the cooperating growers ended the season enthusiastically endorsing the scouting program. Successful implementation of the program industry wide will depend on proving the pest control success and economic viability of the costs of scouting versus the traditional spray programs.
Project goals and objectives
The objectives this program were twofold:
(1) To enlist the active participation of Pacific Northwest growers in a coordinated, area-wide IPM program for leafroller contaminant control in caneberries.
(2) To discuss and analyze the economics of such a program versus the conventional method which would not use monitoring and would include chemical spraying on a calendar basis.
Of the approximately 12,000 acres of caneberries in Washington and Oregon, an estimated 90% are being treated with one to four applications of broad-spectrum insecticide during or immediately before harvest. At the end of the two-year period of this program, a minimum of 800 acres (approximately 7%) of caneberries in southwest Washington and western Oregon will be managed for caneberry harvest contaminants using monitoring tools, threshold development, and IPM decision-making instead of relying on the harvest calendar to apply contaminant insecticides.
The cooperators maintain a website at: www.nwipm.info/