A population of spotted lanternfly (Lycorma delicatula) was recently discovered in Berrien County, Michigan, according to a Sept. 10 announcement by the Michigan Department of Agriculture and Rural Development (MDARD).
Spotted lanternfly (SLF) populations have been found in Michigan since 2022, but only in the southeast parts of the state. This is the first finding in Southwest Michigan, where most of the state’s 13,000 acres of grapes are grown. According to Michigan State University Extension, heavy populations of SLF can weaken grapevines, lower fruit quality and reduce yields.
“The recent detection of spotted lanternfly in Southwest Michigan is a new region of the state and in a county with many grape growers,” MSU entomologist Rufus Isaacs said in a statement. “Thankfully, these spotted lanternflies were found in a park and not on a crop, but growers should continue to monitor for this invasive pest on tree of heaven and their grapevines as they go about their fall activities.”
In addition to the Berrien County detection, a new population of spotted lanternfly was recently confirmed in Washtenaw County in Southeast Michigan, according to MDARD.
For the past few years, Isaacs and other MSU specialists have been monitoring vineyards and surrounding areas for SLF and helping growers prepare for the invasive pest’s arrival. After studying lessons learned in Pennsylvania, SLF’s North American epicenter, Michigan growers now have multiple insecticides registered for use against SLF, including a local-needs label that will allow for postharvest applications, Isaacs said.
The MSU entomologist advises growers to report SLF detections to the Michigan Department of Natural Resources’ Eyes in the Field website (www2.dnr.state.mi.us/ors/Home) or their local MSU Extension office. •
