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Great Lakes
Article:
State weeding out invasive species
By Edward Hoogterp
Booth Newspapers
09/07/03
Acre on acre, the dead, gray stems of a foreign weed stand
head-high in what once was a lush wetland in St. John's
Marsh, just inland from Lake St. Clair.
The plants, called phragmites, have been crowding out
native greenery in the popular wildlife area for more
than a decade. State biologists are fighting back with
a combination of herbicides, fire, giant mowers and water-level
controls.
Contractors for the state Department of Natural Resources
used a helicopter to spray 170 acres of thick phragmites
in the marsh a year ago. The state expects to burn the
area this month to destroy the dry stalks and any young
plants that may be sprouting from the roots.
"When the phragmites get so thick, there really
isn't a whole lot under there to worry about killing,"
said Kurt Getsinger, an invasive species researcher with
the U.S. Army Corps of Engineers.
St. John's Marsh is just one among dozens of sites where
state agencies and nonprofit groups such as The Nature
Conservancy are working to root out invasive weeds and
replace them with plants native to Michigan.
In a process that began with voter-approved funding in
the mid-1990s, state biologists are gradually restoring
hundreds of native plant species in places like Algonac,
Sterling and Grand Mere state parks, the Fort Custer Recreation
Area, Bay City's Tobico Marsh and the Brighton Recreation
Area.
Restoration projects and related research have gained
speed in recent years, thanks to a series of grants from
government and nonprofit agencies, with hunters and conservation
groups providing matching funds.
One budding success is the six-acre Blazing Star Prairie,
inside Algonac State park, where some 200 species of plants
provide a hint of the colors and shapes that once covered
150,000 acres of lake-plain prairies in Michigan.
The purple spikes of the blazing star plants that give
the site its name finished blooming in August. In early
September, the prairie is filled with flowers of ironweed,
tall coreopsis, tall sunflowers, native thistles and rare
Sullivant's milkweed.
"From early spring on, there's something blooming
in there," said Ray Fahlsing, who manages native
species restoration programs for the DNR's Parks Division.
As part of the restoration effort, researchers are trying
to slow the spread of tough weeds such as purple loosestrife,
glossy buckthorn and phragmites, the tall, feathery plants
that have displaced native reeds and cattails along parts
of Lake Huron and Lake Erie.
Crews must take care they don't knock one invasive weed
out of a site, only to clear the way for a worse problem,
Fahlsing said.
That happened in some spots where researchers released
a beetle to control stands of purple loosestrife, which
thrives along streambanks and roadsides. The beetles did
their job, but on some sites the loosestrife was simply
replaced by phragmites, which is even more difficult to
control.
Phragmites is a cause for considerable concern in Ontario
and Eastern Michigan, as well as the Atlantic Coast. The
plant sends out horizontal roots called rhizomes that
can extend up to 70 feet and send up a new stalk every
10-12 inches.
It's tolerant of salt, which gives it an advantage in
roadside ditches, and it survives fire by re-sprouting
from the roots.
A native variety of the plant grows in much of the United
States, including Michigan, without crowding out other
species. Genetic studies show the plants invading Great
Lakes shorelines are all of a single non-native genotype,
Getsinger said.
Ernie Kafcas, a DNR wildlife habitat specialist, said
disturbed land won't return to its natural state on its
own. Even when balance has been restored, it's a never-ending
job to keep out brush and invasive species, he said.
"If you did nothing here for even 10 years, it would
brush right up," Kafcas said recently as he looked
over the Blazing Star Prairie. "You've got to manage
it and you've got to be knowledgeable."
Fahlsing relies on a "huge" volunteer effort
to collect wild plant seeds for use in restoration programs.
Volunteers will be harvesting seeds this year or next
in such widely diverse landscapes as Fort Custer Recreation
Area, Bay City's Tobico Marsh and the Brighton Recreation
Area.
Lake plain prairies such as that in Algonac State Park
are low-lying areas just inland from the Great Lakes,
where the high water table discouraged growth of the forests
that naturally covered much of Michigan.
Before European farmers arrived, native people regularly
burned the prairies to keep them open for wildlife habitat
and for gathering food and medicinal plants.
The small Blazing Star Prairie remnant was choked with
non-native plants, shrubs and small trees when the state
began managing it about seven years ago with periodic
fire, mowing, application of pesticides and seeding of
such native plants as big bluestem grass.
But even here, the plant community hasn't been completely
restored.
Directly across the St. Clair River in Canada, Indians
on Walpole Island are still managing prairies in the traditional
way, with annual burning on land that was never cultivated
for agriculture. There at least 300 native plant species
continue to thrive.
"They have 100 more species than we have over here,"
Fahlsing said.
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