Green Investment – Save MI Hemlocks

Green Investment is an occasional series about the positive impact of Ottawa County parks on the quality of life in West Michigan, presented by the Ottawa County Parks Foundation. 

Residents join parks in all-out war against hemlock bugs

Mary Terpstra checking hemlock trees in her neighborhood.

The sun just edged above the wooded dune to the east as residents of the Forest Beach neighborhood gathered, ready for battle, in Mary and Dale Terpstra’s driveway one recent morning.

Soon, after strategy from Drew Rayner and suitably armed with clipboards, hammers, tags and tape measures, they fanned out for reconnaissance in teams of two.

The neighbors were out to save their hemlock trees from a bug called the hemlock woolly adelgid. Their skirmish is part of a campaign to save eastern hemlocks in Ottawa County parks and in woods from Fennville to Mears. Ultimately, the battle is to stop the spread across Michigan and, in a way, protect Michigan’s outdoors as we know it.

If the hemlock woolly adelgid (HWA) escapes containment here on Michigan’s west coast, it could lay waste to northern Michigan’s hemlock forests. An estimated 170 million Michigan hemlocks are at risk.

Dark, green groves of eastern hemlock are some of the most inviting scenes and quiet spaces of Michigan’s peninsulas. They cool trout streams and shelter deer.

Hemlocks along the Pigeon River by David Michael Lawson

“It’s a critical species in Michigan,” said Melanie Manion, natural resource management supervisor for Ottawa County Parks Department. “If the hemlock dies out, our hunting and fishing go away. It will completely change the aesthetics as well as the economy of Michigan.”

So, it’s war. And as in any war, alliances are crucial.

“We love to see private initiatives like this neighborhood effort,” said Bobbi Jones Sabine, Vice President of the Ottawa County Parks Foundation board of directors.

“The county parks staff and the Parks Foundation do a lot, as much as we can, but it is so much better and more effective with the support and active involvement of a caring community. And that holds true not only for controlling invasive species, but also for our combined efforts to provide and manage green space and natural lands in our county.”

The battle against HWA is one example of cooperative parks system, foundation and community investments that enrich lives with recreation and natural resources.

The hemlock woolly adelgid, related to aphids, came from East Asia to Virginia in the 1950s. They suck sap, eventually killing host trees. The bug has laid waste to vast tracts of the Appalachians and the Eastern seaboard. Michigan seemed safe until the past couple years, when HWA was found in West Michigan.

Terpstra spotted an infestation in her neighborhood a year or so ago. She believes it came in on nursery stock but has now spread to native trees.

There is effective treatment, but HWA spreads fast, Manion explained. So, the neighbors went looking to find any tree with the white wooly mass at the base of its needles.

Rayner, coordinator for the West Michigan Cooperative Invasive Species Management Area, gave them marching orders on how to identify and mark infected trees for future treatment.

His team and the West Michigan Hemlock Woolly Adelgid Task Force are surveying the extent of the infestations. Most are along Lake Michigan or water bodies including rivers, Lake Macatawa and Spring Lake. HWA has been found in the Sanctuary Woods Preserve and the Hope College Forest Preserve and is suspected in other private tracts along the lakeshore.

Drew Raynor instructs neighborhood survey team on finding HWA.

Some property owners are taking action, like Terpstra and her neighbors. Getting enough people working together allows for large-scale, lower-cost treatment. Treatment is highly technical, best left to professionals, but also very effective. Costs average $30 to $50 a tree for a large contract, but size of the tree can impact cost one way or another.

Fortunately, compared to some invasives like emerald ash borer, HWA is relatively slow acting, typically taking seven to 10 years go kill a tree, Rayner said. A tree with HWA that is properly treated can rebound and survive.

But it’s vital to Michigan’s forests that the bug be contained and eliminated in the relatively limited current area, before it becomes unmanageable across the state.

While Maine has a “Slow the Spread” campaign, the battle cry in Michigan is “Stop the Spread,” Manion said. “We don’t want to be the reason the entire Midwest is infected with HWA.”

And that means all-out war, with whatever alliances that can be formed.

How you can help Save Michigan Hemlocks:

  • Check your hemlocks for the identifying white woolly substance on twigs and branches.
  • If you suspect HWA but aren’t sure, you can bring close-up pictures to Ottawa County Parks Nature Education Center, 8115 West Olive Road, or DeGraaf Nature Center, 600 Graafschap Road in Holland. Do not transport samples, which can spread the disease!
  • If you believe you have HWA on your property, email or text photos to Drew Rayner at hwa.crew@macd.org or (616) 402-9608 so his group can document it.
  • Join in a collective treatment plan for your property or neighborhood and contract with a reputable company.
  • Limit the spread by trimming back hemlocks where you park vehicles or along driveways, and where you or your dogs hike. It can transport on anything that touches it.
  • Support the West Michigan Hemlock Woolly Adelgid Task Force with private donations to match state grants; donations possible through the Ottawa County Parks Foundation.
  • Go to savemihemlocks.org for close-up photos, more information, details and instructions for all these steps.