29-04-2025
Efforts continue in battle against invasive water chestnuts
Apr. 29—Efforts are continuing to battle the spread of the invasive water chestnut plant in the Oswegatchie River, Black Lake and most recently, the St. Lawrence River.
Brad Baldwin, a professor of biology at St. Lawrence University, has been working with Heuvelton and town of Oswegatchie officials and volunteers in an attempt to reduce the population of water chestnuts near Heuvelton and to prevent their spread into neighboring bodies of water.
However, Baldwin reports that three small infestations of the invasive plant were found in Black Lake and another small pocket was found in Tibbets Creek, located just downstream of Ogdensburg in the St. Lawrence River.
The water chestnut plant, Trapa natans, is a highly aggressive invasive aquatic plant found in lakes, bays, canals, and slow moving rivers with muddy bottoms. The plant was likely introduced to North America as an ornamental plant for its unique size and shape. The St. Lawrence-Eastern Lake Ontario Partnership for Regional Invasive Species Management, or SLELO PRISM, based in Pulaski, has stated that the aquatic plant poses a significant threat to the ecology of the state's waterways and requires significant resources for annual management.
Baldwin agrees.
The invasive plant can impact boating, fishing and can negatively impact shoreline residents where it is found, such as in Heuvelton on the Oswegatchie River.
"Where chestnuts are thick, as at Heuvelton, recreational uses such as boating and fishing, are nearly blocked. And for all the shoreline residents out there, if you thought dealing with invasive water milfoil was bad, this new water chestnut plant is far worse," he said.
The biology professor will not only be assisting in the water chestnut removal, but will be studying its effect on underwater environmental conditions on fish life.
FUNDING EFFORTS
The effort has received funding over the past several years.
The state Department of Environmental Conservation (DEC) awarded a three year $99,000 grant, from 2024-2026, and another grant for $15,000 was received by the St. Lawrence River Research and Educational Fund (SLRREF) through the New York Power Authority (NYPA) in 2024. The town of Oswegatchie had also received a DEC grant in 2024 to assist with efforts and a mechanical harvester was purchased.
The effort has received another $15,000 grant this year from the SLRREF program to fund work on eradicating a small populations of water chestnuts in a small embayment of the St. Lawrence called Tibbets Creek.
TURNING A CORNER
"Collectively, our efforts at Heuvelton focus on removing the thick chestnut weedbeds at Heuvelton using mechanical harvesters," stated Baldwin," As you may know, the chestnut plants have been building populations there since about 2020 and became too large to control by the hand-pulling efforts gratefully attempted/organized by the SLELO PRISM teams, who continue to help downstream of Heuvelton, toward Eel Weir Park."
Earlier efforts by entities such as the Black Lake Association and other contributors funded mechanical harvesting efforts in 2022 and 2023. The increase in funding has allowed an increased amount of water chestnut harvesting, according to Baldwin.
"With the influx of grant money, we really picked up the pace of harvesting and cleared about 90% of the approximately 40 acre infestation at Heuvelton," he said.
Baldwin said that those efforts cleared a lot of space for recreational boating/fishing and prevented the production of perhaps 85 million new seeds or nuts in 2024 that would not be able to spread to other bodies of water.
"I think we turned an important corner in 2024 and will continue to run down the Heuvelton population over the next two years," said Baldwin, "I'm optimistic this will become a 'good news' story, where we, along with the crucial help of local community volunteers, will restore some of our crucial natural habitats."
TIBBETS CREEK INFESTATION
The infestation found in 2024 in Tibbets Creek appeared to be small, about the size of a small yard, according to the biology professor.
The invasive plants found were "rooted, mature, and producing new nuts, which means these plants can flourish in quiet, muddy bottom bays, tucked just inshore." Luckily, most of the river itself has rockier bottoms and a higher current that the water chestnut does not like.
Most of the water chestnut infestation were removed in 2024, according to Baldwin, who stated that he, along with volunteers, Dalton Miller and Dave Richardson, will return "to remove any additional plants we find."
The latest SLRREF grant will also fund additional shoreline surveys, from Ogdensburg to Massena, for water chestnuts as well as allow for scientific studies on the value of native underwater vegetation for fish.
"We sure don't want the plant to infest other shoreline bays of the river which are crucial nursery areas for fish. Thankfully we have a new 2025 grant from the SLRREF program to fund this work," Baldwin said.
The St. Lawrence River infestation may have been caused by chopped up plants from Heuvelton that had drifted downstream on the Oswegatchie River and made it into the St. Lawrence due to two high flood incidents last summer.
THE KEY TO VICTORY: VOLUNTEERS
Efforts will not begin for the 2025 water chestnut program until the weather and water levels improve. Baldwin expects efforts to begin mid-May.
Volunteers will be needed to assist, not only with their removal, but by keeping their eyes open for the invasive plant species.
"Local volunteers are the keys to victory! The more eyes on the water the better. I have already taught several persons how to identify the plant and pull them out by hand. If we can multiply the number of folks who can do the same, we can nip this in the bud and protect the shoreline values we depend on," said Baldwin.
Anyone interested in assisting can email Baldwin at bbalwin@
