MAYVILLE - Just how dangerous are water chestnuts, an aquatic invasive species thriving in the Northeast? Look no further than Lake Champlain in Upstate New York.
"Water chestnuts have been well established in Lake Champlain for a long, long time," said Fred Dunlap, Lake Champlain coordinator for the state Department of Environmental Conservation. "It's a very invasive plant that makes recreation, swimming and boating very difficult."
The plant, which was recently discovered in Chautauqua Lake and Lake Erie, forms dense surface rosettes, crowding out other vegetation species, Dunlap said.
Water chestnut forms thick mats of leaves on the water’s surface, making navigation and recreation difficult.
Photo courtesy of the Lake George Association
If not found in time, one acre of water chestnuts produce enough seeds to seed 20 acres the following year. Primary means of control are mechanical harvesting and hand-pulling - a method that has proven successful in the north state.
"Our harvesting begins in July and goes right through the summer until Labor Day," Dunlap said. "The water chestnut comes back every year. We just try to maintain it."
He added, "Overall we're winning the battle. If you don't get the funding and you miss a year you have a lot of catching up to do. One year missed will set you back years."
To maintain the pesty plant, New York state has partnered with Vermont - a move that has slowed the growth of water chestnuts in recent years.
But even with state and volunteer help, managing the plant has become an expensive venture, to the tune of millions of dollars.
Since 1982, New York state alone has spent $735,000 for water chestnut management on Lake Champlain, according to a 2009 report by the Vermont DEC. In total, over $8 million has been spent on the lake, which includes funding from both states and the Army Corps of Engineers, the report states.
Chautauqua County officials have taken notice with infestations in other lakes.
"We have been in contact with the DEC regarding the plants in other lakes, especially Lake Champlain," said County Executive Greg Edwards. "We are using their knowledge to help us understand what we have here and what to do to eradicate this plant."
A consulting firm recently found portions of a water chestnut plant in Chautauqua Lake while performing a dredging feasibility study.
The discovery prompted Edwards to immediately call a press conference and establish a toll-free hotline for residents to report any sightings.
That hotline paid off immediately as a kayaker discovered a rooted plant 50 feet off the Bemus Creek shoreline. Jeff Diers, county watershed coordinator collected the plant and confirmed it was the first rooted plant found in the lake.
The plants have also been sighted in Dunkirk Harbor on Lake Erie. It's unknown at this time how many plants were discovered there.
The water chestnut is an annual aquatic plant that has submerged leaves and can reach 12 to 15 feet in length. The plant also has a rosette of floating leaves, which are green, glossy and triangular with toothed edges.
It is believed that the plant has spread through the Northeast, infesting at least 80 waters in New York state.
If water chestnuts are spotted residents are asked to call the county's hotline numbers: North County: 363-4499; Mayville: 753-4499; or South County: 661-7499.
Residents are also encouraged to attend a mass-search at 8 a.m., Tuesday at the Bemus Point-Stow Ferry landing.
"It's unfortunate they found the plant" Dunlap said, "but it's good they found it now so they can take care of it before it spreads."