Caseload at the UW Insect Diagnostic Lab (IDL) has been high, but decreased slightly over the last two weeks.  A summary of recent fruit crop insects reported to the lab as well as important insects to scout for can be found below:

Stink bugs: Stink bugs have been the top fruit-crop insect reported to the UW Insect Diagnostic Lab recently.  Both nymphs and adults of the brown marmorated stink bug and the green stink bug have been common around the state in a wide range of fruit-crop and other settings.  Beneficial, predatory stink bugs (e.g., Podisus, etc.) have been reported as well.

Japanese beetles: Japanese beetles reports have dropped off substantially over the last two weeks.  Almost all recent reports at the IDL have been from northern Wisconsin on fruit trees and raspberries.

Pearleaf blister mites: I’ve recently had several samples of pearleaf blister mite.  These tiny eriophyid mites are associated with dark, scab-like areas on the leaves of pear and certain other fruit trees this time of the year.  To confirm their presence, the lesions must be dissected under the microscope to check for the presence of mites.  Their damage can be common but generally doesn’t have much of an overall impact on tree health.  Once mites colonize leaves early in the growing season, pesticides have a hard time targeting the mites which live within leaves.

Social wasps: We’re reaching peak season for colonies of yellowjackets and paper wasps.  If abundant, these can pose sting concerns at the time of harvest and in U-pick situations.  Activity is expected to remain high for another month or longer depending on weather patterns.

Bumble flower beetles: I often see reports of bumble flower beetles in spring and again in late summer and fall and have had recent reports from southern Wisconsin.  These scarab beetles resemble small, fuzzy May/June beetles with a mottled black and brown coloration.  They are opportunistic scavengers that love sugars.  They often show up at damaged/compromised fruits as well as vegetables and even compost piles.

Reminder about diagnostic support from the IDL: Growers and consultants in need of insect diagnostic services are always welcome to submit a sample to the UW Insect Diagnostic Lab.  Lab services are provided free of charge.  You can find additional information about the IDL here: insectlab.russell.wisc.edu

This article was posted in Insects and tagged bumble flower beetles, Insect Diagnostic Lab, insects, Japanese Beetles, pearleaf blister mite, PJ Liesch, social wasps, stink bug.