Groups battle invasive species at St. Johns Marsh
Clay Township, Mich. — Drive along the Dyke Road in Clay Township, and the landscape looks a prototypical marsh — massive beds of tall reeds waving like banners against a blue sky.
But what you’re seeing shouldn’t be there. The reeds are an invasive species, non-native Phragmites australis, that, like the bully on the block, has driven out the native species and left little room for wildlife.
Terry McFadden, a Michigan Department of Natural Resources biologist, describes phragmites’ impact in terms generally reserved for much drier ecosystems.
“It’s basically a biological desert within the core areas,” he said, explaining that not much else grows where phragmites, or common reed, has taken hold and that the stands of the giant reed — plants can reach 15 feet tall — offer little access for waterfowl and other wildlife.
The plant also limits recreational used to channels cut through the dense patches of vegetation.
“The marsh is beautiful,” said Kris Dombrowski at Great Lakes Docks & Decks. “And all we get to do is drive by it.”
The state, with help from Clay Township and several wildlife groups, wants to change that. The partners have launched a $1.6 million project to reclaim about 627 acres of St. Johns Marsh from the grasp of invasive species.
Jason Hill, a biologist with Ducks Unlimited, said the goal is to return that part of the marsh to what it looked like pre-phragmites.
“My vision is when this project is done and the initial treatment is done is the replication of native vegetation interspersed with open water,” he said.
Phragmites is one of at least 184 non-native aquatic plants, animals and insects that have established themselves in the Great Lakes region. It probably was brought to North America in the late 1700s or early 1800s, according to information from Michigan State University.
It’s a member of the grass family. It can spread through its seeds, the large plume-like seed heads are one of the most visible features of the plant, and via an underground system of rhizomes.
It was used extensively in its native Europe to make thatched roofs and, according to information from MSU, once established it is nearly impossible to grub out by hand.
“Getting rid of the phragmites is kind of a helpless cause,” said Jerry Gordon, a waterfowl hunter from Algonac and a member of St. Clair Flats Waterfowlers Inc. “They started 40 years too late.”
Clay Township since 2010 has waged battle against the reed, establishing in that year a township Phragmites Advisory Board. Jan Zeboril is a member of the board and he describes phragmites as a tough foe.
“You just can’t get it done in one year,” he said. “It takes three years depending on how thick the infestation is.”
The Michigan Department of Environmental Quality recommends a multi-pronged approach to phragmites control — spraying with an herbicide such as formulations of glyphosate approved for aquatic use, burning to remove the dead biomass, and flooding to drown the roots.
“You want to spot treat when you see something popping up,” Zeboril said.
Brian King, owner of Blue Water Bait in Ira Township, said one of the keys to phragmites control is staying on top of the situation.
“They need to stay on it,” he said. “Let it go for a couple of ears, and the phrags come back.”
The DNR’s McFadden emphasizes the St. Johns Marsh project is about controlling invasive species — not just phragmites control.
“What we’re trying to do is, we’ve been dealing with invasive species for a long time,” he said. “It started out with purple loosestrife and then phragmites that has been an ongoing cycle of spray and burn.”
He said managing water levels in areas such as the marsh results in better control of invasive species. Managers can drop the water level to treat and burn, then let the water back in to drown the rhizomes.
“We were looking at St. Johns Marsh trying to figure how to improve our efficiency dealing with wildlife issues,” he said. “We came up with a project that would utilize some of the old infrastructure, the old dikes, restore those dikes, put a pump in.”
The goal, he said, is “restoring quality wetlands as opposed to dealing with an ongoing cycle of treatment and spending a lot of money dealing with invasive species.”
There will be some money spent: The project is being funded with part of a nearly $600,000 grant from the U.S. Fish and Wildlife Service to improve 380 acres of coastal wetland in Michigan and Ohio. The money will be used to improve St. Johns Marsh and the Toussaint Wildlife Area in Ohio.
Clay Township will provide $10,000 as will the Michigan Duck Hunters Association. The St. Clair Flats Waterfowlers Inc. will kick in $100,000, and Ducks Unlimited will contribute $450,000. The DNR’s share of the project comes to $125,000.
The marsh’s unique history means there already is some infrastructure in place that will expedite the project. It was developed by Will St. John in the 1930s from the Pointe Tremble Prairie as an 18-hole golf course to complement the Colony subdivision.
It was turned into a sugar beet field during World War II. After World War II, there were some effort to restore the golf course, but eventually, it was allowed to revert back to a marsh. The entrance to the golf course off the Dyke Road still exists, marked by a monument for the St. Johns Marsh Wildlife Area erected by the state.
About 332 acres to the north of the monument will be managed as a new coastal wetland area by building new or restoring existing dikes. Construction also will include water level control structures, a fish passage structure and a pump.
Work on that part of the marsh will allow more water and improved management of an additional 295 acres of wetlands, according to information from Ducks Unlimited.
Ducks Unlimited already has completed the engineering feasibility and design process for the St. Johns Marsh project. The group recently applied through the DNR for permits from the US Army Corps of Engineers and the state DEQ to begin work in the marsh.
Work would include mechanically dredging existing ditches in the wetlands, using the dredged material to build 2.5 miles of dikes, installing a pump and water control structure in the dike to manage water levels and allow fish passage, and building a temporary haul road to dredge 1.5 miles of existing canals.
The project also would entail dredging 150,000 cubic yards from 20.4 acres of the marsh to create 17.9 acres of dikes, leaving 332 acres of marsh and shallow water.
Ducks Unlimited’s Chris Sebastian said the partners are not sure how long the permitting process will take.
“We hope to have permits in hand this year and start to break ground,” he said.
Hill said the ideal situation would be to obtain the permits within the next three to six months, bid out the project and start construction work in the fall.
“We’re probably looking at a completion time sometime in 2018,” he said. “When it’s complete, it’s still going to take a little bit of time: Spray the phragmites that’s out there, burn it and spot treat it.”
John Darling is a DNR biologist at the St. Clair Flats Wildlife Area, which includes parts of Harsens Island, St. Johns Marsh, Dickinson Island and the Flats. The area has long been crucial for migratory and resident waterfowl, he said.
“Lake St. Clair and western Lake Erie are the main places where the Atlantic Flyway and the Mississippi Flyway come together so we get birds from both flyways,” he said, explaining that flyways are migratory paths followed by birds in the spring and fall.
“I wouldn’t have a real good estimate on total numbers that come through,” he said. “... When they fly, the diver duck surveys out on the lake; it’s not uncommon to have multiple hundreds of thousands of divers — canvasbacks, redheads and scaups or bluebills.
“They’re primarily feeding on vegetation,” Darling said.
He said the biggest resident populations are of mallards and wood ducks.
“Phragmites is occupying the emergent wetland areas where traditionally mallards especially would be trying to nest,” Darling said.
“The divers would stay out on the big water, but almost every puddle duck would be impacted by invasive species,” he said. “Native plants such as wild rice and other food sources would eventually be taken over by phragmites, which provides zero food source for a duck.”
Brendan Shirkey, research coordinator at the Winous Point Marsh Conservancy in Port Clinton, Ohio, in 2012 completed his masters thesis at MSU regarding diving duck abundance and distribution on Lake St. Clair and western Lake Erie. He said Lake St. Clair is “incredibly important” for waterfowl.
“Our surveys estimated that during peak migration there might be in excess of 500,000 diving ducks on Lake St. Clair and the adjacent wetlands. Importance would primarily be to migrant birds, but there are likely some local breeding ducks as well (mallards and wood ducks),” he said.
Phragmites and other invaders, he said, reduce biodiversity.
“As a result, there’s the potential for a significant drop-off in the value of a wetland as wildlife habitat,” he said.