–by Dr. Bob Bauernfeind
Japanese beetles have become a firmly established pest species in portions of Kansas. Potential damage is twofold. Most commonly, Japanese beetles indiscriminately feed on nearly 300 plant species including fruits, vegetables, agronomic and forage crops, ornamentals, trees and shrubs. Often times, host plants are literally covered with the gregarious beetles which rapidly consume any and all foliage and floral plant tissue. A second type of damage is associated with the “white grub” larval stage as a potential turf pest.
While some individuals prefer to calculate/record accumulated Growing Day Degrees50 as a method to predict the initial yearly appearance of Japanese beetles, one can more easily set out traps baited with the JB pheromone and floral lure. The bonus is that this also tells an individual that JB actually are “in-the-neighborhood” as evidenced by their being captured.
First 2015 reports of JB captures: Desoto June 9; Manhattan June 15; Topeka June 16. Look for their numbers to rapidly increase. People concerned with JB feeding on landscape plants need to be vigilant in inspecting plants for the presence of JB. If present and if in damaging numbers, corrective actions should be undertaken. Refer to K-State Research and Extension Publication MF3151 – Japanese Beetle, which is available and downloadable on-line.