(WWJ) — Officials with the DNR are asking Michiganders to be on the lookout for an invasive species that can “cause significant harm” to more than 150 million trees across the state.
The Michigan Department of Agriculture and Rural Development recently verified a new detection of the invasive hemlock woolly adelgid near Torch Lake, on the east side of the Grand Traverse Bay in Northern Michigan.
MDARD officials say the extent of the infestation is not yet known, but they are conduction “an extensive survey of the surrounding area.”
This latest detection makes Antrim County the seventh in Michigan with an active hemlock woolly adelgid infestation, joining Allegan, Benzie, Mason, Muskegon, Oceana, Ottawa, and Washtenaw Counties, according to the DNR.
Hemlock woolly adelgids are small insects that “use their long, siphoning mouthparts to extract sap from hemlock trees,” according to the DNR. Their feeding weakens needles, shoots, and branches.
Over time, tree growth slows, and trees take on “a grayish-green appearance,” the DNR says. Without treatment, infested trees die within four to 10 years.
If left unchecked, the invasive insect can “cause significant harm to Michigan’s estimated 170 million hemlock trees,” said Steve Carlson, MDARD’s Pesticide and Plant Pest Management Division Director.
The new infestation was found by a landowner who learned about the hemlock woolly adelgid while attending an educational outreach in Northern Michigan, according to Carlson
“Situations like this demonstrate the importance of public awareness in our fight against invasive species,” Carlson said.
The DNR says hemlock woolly adelgid can be identified by looking on the undersides of hemlock branches for evidence of round, white ovisacs near the base of the needles. Up close, ovisacs look like balls of spun cotton and may appear alone or in clusters.
Other, less damaging pests easily can be mistaken for hemlock woolly adelgid, DNR officials said, so it’s important to review photos and descriptions of common hemlock woolly adelgid look-alikes at Michigan.gov/HWA. Help in identifying eastern hemlock trees is also available at the same site.
“Hemlock woolly adelgid likely arrived in Michigan on infested nursery stock from northeastern states. Though the tiny insects don’t move far on their own, they can be blown by wind or hitchhike on animals,” Carlson said
“In a similar way, cars, boats, or RVs parked under infested trees may be able to transport the insects to new locations,” he added. “If you’re headed outdoors, take simple measures like only parking in designated areas and cleaning your gear and vehicle before traveling. Also, remember to leave firewood at home and buy it locally at your destination.”
Suspected infestations in Antrim County or new areas of the state can be reported by:
Emailing MDARD at MDA-Info@michigan.gov or calling the Customer Service Center at 800-292-3939.
Using the Midwest Invasive Species Information Network (MISIN) online reporting tool or downloading the MISIN smartphone app and reporting from your phone.
Be prepared to report the location of infested trees and, whenever possible, take one or two pictures of infested branches to help confirm identification. To avoid spreading hemlock woolly adelgid, do not collect sample branches or twigs.
For more information on hemlock woolly adelgid and other invasive species in Michigan, and to find out what you can do to help prevent them, visit Michigan.gov/Invasives.