Lacanobia fruitworm is best sampled with a limb jarring procedure that knocks larvae onto a white sheet for counting. Lacanobia prefers the young, vigorous growth near the top of the tree. It is a nocturnal feeder, although it does remain in the canopy throughout the day. Scouting for lacanobia can be labor intensive, but those growers who have had a problem in the past or live next to someone who has experienced problems with lacanobia should make that effort. In summary, the lacanobia fruitworm is an emerging pest problem in apples in some areas in the Pacific Northwest.
Effective management is achievable if growers are proactive in their efforts.
Frequently, by the time the problem is evident, the mature larvae have become more tolerant to pesticides that are effective against them as young larvae, or the preharvest interval restricts product use. If you or a neighbor has encountered a problem with lacanobia in the past, prepare yourself to scout and manage the pest this year. Newly hatched and young larvae are quite susceptible to a number of insecticides, some of which fit in quite well with an effective integrated pest management system that promotes natural biological control of key pests. Bush is a WSU Cooperative Extension educator in tree fruit for Yakima County.