Leafroller damage within the project increased in 1995, the first year mating disruption was used, but declined in 1996. Asked how long it takes to hang the pheromone dispensers, Richardson said they were applied throughout the 378 acres of the project in seven days. In widely spaced orchards with large trees, more than one dispenser per tree may be needed. He said tree density in the Osoyoos project ranges from 54 to more than 1,700 trees per acre. In view of the low codling moth populations, some growers plan to use only 200 dispensers per acre this season.
Figures are averages.