Twin Lakes: Invasive water plant prompts new alert

SALISBURY – No, you cannot roast them on an open fire, nor will you find them in your takeout order of Asian food. The kind of water chestnuts the Twin Lakes Association (TLA) last week issued a warning about are of the thorny, non-edible, invasive variety that can destroy a lake’s ecosystem and put a serious damper on recreational activities.

The Twin Lakes Association posted an alert via its newsletter June 1 about a “potential new invasive weed” that has come to its attention. On May 18, two hard and spiny water chestnut seeds were found on the dock at the marina’s boat launch.

While an immediate inspection of the area by state officials did not turn up any living plants, the TLA is asking the public to keep an eye out for signs of the invasive weed or pods, which they said may have floated away and deposited seeds elsewhere.

Matthew Goclowski, a Supervising Fisheries Biologist with the state Department of Energy and Environmental Protection (DEEP), said aquatic water chestnuts, he said, are not to be taken lightly.

“It is definitely a real threat. Water chestnuts have the potential to cover the surface area over large bodies of water. They can make boating and fishing and all sorts of water activities very difficult,” the DEEP official explained.

He said the leaves from the plants form dense mats on the surface of the water, shading out submerged plants. Its seeds can be viable “for quite a long time, about seven to 10 years” if they remain moist and do not dry out.

Spotted by a keen-eyed
fisheries expert

Russ Conklin, a member of the TLA, said the two dried water chestnut seeds were discovered on April 18 by retired DEEP fisheries official Ed Machowksi while stocking salmon yearlings in East Twin Lake. “No one else would have recognized them,” Conklin said.

The big question, said Conklin, is “Was that the only one that got here? Our belief is that this will not present any problem,” as the seeds were dried out and did not appear viable.

The lake association is asking visitors and lake property owners who find either the weed or the pod, to take a photo and report the finding to the DEEP, and to dispose of it in the garbage, not in a mulch pile where it might find its way back to the water.

Photos should be sent for documentation to DEEPAquaticinvasiveReport@ct.gov.

“Our belief is that somebody saw this thing, which is kind of unique, picked it up and put it in the boat,” and then left it behind on the dock, said Conklin.

“That’s how they get in. The plants don’t generally get stuck to the boat, they get into the boats through bilges or bait wells.”

DEEP’s Goclowski said boat owners should be diligent in checking their watercraft and trailers for signs of invasives, including zebra mussels and water chestnuts, both before going into the water and again when leaving.

According to state law, “Boaters must inspect their vessel for vegetation and aquatic nuisance species and properly remove and dispose of all vegetation and nuisance species before transporting the vessel.” Offenders can be fined $95 per violation.

Conklin pointed to an infestation of water chestnut that took place in Long Pond in Salisbury in 2019 that is still problematic today

Boat washers
seen as ineffective

According to Bill Littauer, president of the Lake Wononscopomic Association, so far aquatic water chestnuts have not shown up on Lakeville Lake, but the situation is being monitored.

The association bought a hot water washing machine more than 23 years ago that was installed at State Line Car Wash in Lakeville.

“Fishermen who arrived at the town Grove launch site with boats and/or equipment that indicated they had not dried out after launching in another body of water were refused entry until they had washed their boats and eliminated any invasive species,” said Littauer. “Few boaters took advantage of the washing machine and it wasted away.”

TLA’s Conklin said, in general, he does not support the use of boat washers when it comes to invasive species. “If you’re talking about creatures, yes,” he said, referring to the presence of invasive zebra mussels which attach themselves to the outside of watercraft.

The other problem, he said, is lack of enforcement.

The boat ramp is open after hours at the marina, so there is no one there to enforce cleaning before entering the water. The state launch is unmanned and there would need to be additional screening to keep whatever gets washed off a boat from entering the water, said Conklin.

“Fishermen come to the launch late in the evening and fish all night. That doesn’t work with a washer, plus it’s not the place to do it.”

How to identify invasive water chestnuts

Water chestnuts (Trapa natans) are easily identified by their triangular shape leaves that float at the water’s surface. The leaves form a rosette around a central point, are annual plants with hollow, air-filled submerged stems that extend a length of 12 to 15 feet. Fine roots anchor it to the soil.

Timothy Abbott, Regional Director, Land Conservation & Greenprint at the Housatonic Valley Association (HVA) based in Cornwall Bridge, said the water chestnut was an incipient invader of Columbia County lakes about 20 years ago and has been spreading in our region since 1998.

“Bantam Lake first recorded it in 2002. In Sharon and Salisbury, Beeslick Pond has had it since at least 2006, and Mudge Pond since at least 2015,” noted Abbott, who is slated discuss best practices for maintaining the health of the lake at the Twin Lakes Association’s membership meeting on June 18.

“Water chestnuts are one of the species that is more obvious because they have a large floating portion to them and are relatively easy to remove” by yanking them out in massive clumps, said Goclowski.

“The problem is, once you recognize you’ve got it, you’ve got it, and it’s very difficult to get rid of,” Conklin said.