Keep Japanese beetles from clustering on plants and you’ll reduce the signals to their pals to join in the munch fest. Photo courtesy Purdue University
Early arrival of Japanese beetle is expected this year due to the warmer than normal spring temperatures, says Steve Mayer, Extension Educator-Horticulture, for Purdue Extension-Marion County.
“Adult Japanese beetles typically don’t appear until early to mid-June in central Indiana, but this year it will be different,” he says. A weather-based model for Japanese beetle emergence predicts that the first beetle could arrive in Indianapolis as early as May 20, 2012.
Adult Japanese beetles are aggressive foliage feeders of more than 300 different species of plants. Popular targets include roses, Japanese maple, linden trees, grapes and many flowers.
Established, healthy woody plants and flowering perennials will not be killed, but can suffer extensive foliage or flower damage, resulting in aesthetic loss.
Monitor linden trees (Tilia), smartweed (Polygonum pensylvanicum) or other preferred plants to detect Japanese beetle presence. If practical, pick off beetles as they arrive and the initial damaged foliage. This will remove signals that can attract more beetles. To kill the beetles, drop them into a container of soapy water.
Gardeners who have specific questions about Japanese beetles can contact the Purdue Extension-Marion County Master Gardener AnswerLine, (317) 275-9292 or e-mail marionmg@purdue.edu
I haven’t even thought of looking for Japanese beetles yet!