David Owens, Extension Entomologist, owensd@udel.edu
If you have not already done so, begin scouting for San Jose scale crawlers. We placed pheromone traps in several orchards to help time when to expect crawlers, but did not catch any. This does NOT mean that they are not present. Based on previous years’ catch dates and degree day timing, crawlers should have just begun to emerge in the southern portion of the state, and a report came in mid-week of crawlers on black electrical tape. Crawlers will peak at about 500 degree days. Extension recommendations from other states suggest that if you have had weakened trees or observed fruit infestation last year, a treatment is advisable roughly a week after crawlers appear on tape samples.