Pest Alert №4 — Japanese Beetles
Japanese beetles (Popillia japonica) are not welcome, but we have to deal with them each year don’t we? Our first initial sightings of adult beetles in Chicago started to trickle in last week. Today, one held still long enough (snap) with the help of a superintendent’s hand. That snap was the photo. Thank you AD
Importance. Japanese larvae (grubs) feed on the roots of all turfgrasses. They have become the dominant grub population in the landscape that negatively impacts golf courses, lawns, parks and cemeteries in the northeastern US. If preventive measures are not taken, significant root loss and turfgrass damage can occur by the fall.
Interestingly, a majority of the damage isn’t due to a loss of roots and associated wilt and browning of turfgrass areas. Instead, it is caused by the small mammals that feed on the grubs like skunks and raccoons. It you haven’t experienced imagine a mini-trencher digging up areas of your lawn in the middle of the night while you are asleep in say late September.
Reference. It turns out our neighbors to the south, Purdue University, had reported 1st sighting of Japanese beetles about a month earlier (June 17). Which makes sense as they likely have experienced warmer conditions thus far vs Chicago suburbia = we all gain insights by sharing pest information.