The Hydrilla Menace: Twin Lakes group buoyed by DEEP’s assault on invasive hydrilla in 2025

The Hydrilla Menace: Twin Lakes group buoyed by DEEP’s assault on invasive hydrilla in 2025

A detail of a whorl of hydrilla pulled from the shallow waters at O’Hara’s Landing Marina in fall of 2024.

Photo by Debra A. Aleksinas

SALISBURY — The Twin Lakes Association is taking an earlier and more aggressive approach to fighting the spread of invasive hydrilla in East Twin Lake by dosing the whole northeast bay, from May through October, with low-level herbicide treatments instead of spot treatments.

The goal, said Russ Conklin, the TLA’s vice president of lake management, is to sustain herbicide concentration over the 2025 growing season.

That plan of attack will continue over a period of 60 to 90 days beginning May 21, Conklin explained during the association’s April 30 membership meeting via Zoom which drew 60 attendees.

TLA officials were encouraged by the chance to stop the spread and hopefully destroy the thick mats of the unyielding invasive plant hydrilla verticillata, referred to as the Connecticut River variant, after two years of chasing new growth around the lake’s north bay.

Dense patches were first discovered in the summer of 2023 in shallow waters around O’Hara’s Landing Marina and the nearby state boat launch and the plant has since migrated further into East Twin, following a pattern of boat traffic.

Past treatment efforts were hampered by delayed permits from the state Department of Energy and Environmental Protection to treat the hydrilla with herbicides in an area where a rare plant had been identified.

This year, the TLA was granted an exception by DEEP, said Conklin, as any protected plant species in the path of hydrilla would likely not survive anyway.

“It is not dead now, but it is going to be if we don’t do something about the hydrilla.”

“This is a big year for us,” Conklin said. “Hydrilla is a real threat to the lake, and we did treat it this past year, but the permits only applied to the plant, so we spot treated it … and were always chasing it.”

The course of action this year, he said, is to treat the entire northeast bay with the herbicide Sonar in both liquid and crystal form at a very low levels so that the herbicide’s contact time with hydrilla will be extended for a longer period over 60 to 90 days.

“We know from past experience that it is much easier to kill the plant when it’s small,” Conklin explained. The goal, he said, is to attack the stringy, green weed before August when it crowns and splits into numerous growing points that are capable of growing at the rate of an inch a day.

During the hour-long meeting, discussion also focused on a pilot program for enhanced cyanobacteria monitoring at Twin Lakes to be headed by TLA director Jessica Swartz, a resident of West Twin Lake and biotech executive with Pfizer.

“It’s very visibly challenging to identify cyanobacteria blooms,” Swartz explained, as it can easily be confused with pollen on the surface of the water, dead vegetation or different types of algae.

Cyanobacteria, also known as blue-green algae, are natural, important phytoplankton in lake ecosystems. Dense blooms, which release toxins, occur when there is an abundance of sunlight, elevated phosphorus levels and warm temperatures.

Given the current escalation in overly-nutrient rich waterbodies and rising temperatures due to global climate change, the frequency of cyanobacteria blooms is increasing, said Swartz, and Twin Lakes has occasionally experienced localized blooms.

As a result, the association will be implementing a pilot testing program with greater frequency and at more locations than currently conducted by the TLA’s limnologist, George Knoecklein. The goal of the pilot program is to work out the process of collecting reliable data over time that helps inform whether cyanobacteria blooms are occurring, where they are most frequently found, and assess the level of risk.

Sample test kits have been ordered for five or six testing sites across East and West Twin, including at the private Salisbury School.
TLA president Gant Bogle invited Swartz to give an update at the association’s upcoming June 14 membership meeting at Camp Isola Bella.

Despite rising lake management costs projected at $500,000 this year, Bogle reported that the TLA is in strong shape financially heading into the 2025 season, as it received another $75,000 grant from DEEP and $25,000 from the Bates Foundation to support the Watershed Study.

Also, the town of Salisbury has earmarked $75,000 for Twin Lakes this season, said Bogle, and the TLA membership has “responded generously” contributing more than $300,000 since August 2024 when the group started its 2025 fundraising campaign.

Bogle also encouraged members to attend the May 12 public meeting of the Salisbury Inland Wetlands & Watercourses Commission, which is expected to address proposed changes to the Upland Review Area encompassing the town’s lakes.

Latest News

Village will not pursue local ICE law; police say they will cooperate with federal agencies

Village of Millerton and Town of North East residents crowded into the NorthEast-Millerton Library annex to have their voices heard on police policies regarding immigration enforcement for the Tuesday, July 29, Village Trustees meeting.

Photo by Aly Morrissey

MILLERTON — After a packed public meeting brought immigration enforcement to the forefront of village politics on Tuesday, July 29, trustees signaled they will not pursue a proposed local law aimed at limiting police cooperation with U.S. Immigration and Customs Enforcement.

Local police, for their part, said they would fully cooperate with federal agencies — including ICE — tempering hopes for the kind of change some residents had called for.

Keep ReadingShow less
Deputies respond to downtown Amenia political dispute

Kimberly Travis, right, during the early days of her daily "No kings" anti-Trump administration protests at downtown Amenia's Fountain Square in front of the Bank of Millbrook on Saturday, July 5. Travis has become a regular fixture on downtown Amenia after weeks of the daily protests.

Photo by Leila Hawken

AMENIA — Dutchess County Sheriff’s Deputies broke up a political dispute between two Amenia residents at Fountain Square in downtown Amenia on Tuesday, July 15.

Kimberly Travis of Amenia was conducting her daily “No Kings” anti-Trump administration protest at Fountain Square at 1:15 p.m. when Jamie Deines of Amenia, a candidate for Town Board in the Nov. 4 election, approached her.

Keep ReadingShow less
Oblong Books to celebrate 50 years with block party bash

Dick Hermans in the Oblong Bookstore on Millerton's Main Street in 1985.

Photo provided

MILLERTON — To celebrate its golden milestone, Oblong Books is throwing a “good old-fashioned block party” this Saturday, Aug. 9, from 11 a.m. to 4 p.m. on South Center Street in Millerton. The free, family-friendly event will feature live music, food trucks, raffles and entertainment for all ages.

While the festivities mark 50 years since the founding of Oblong Books, co-owner Suzanna Hermans sees the party as something more. “We want to celebrate our friends, neighbors and generations of customers who have kept us here for 50 years,” she said. “It’s a thank-you to the people of Millerton, in particular, without whom we’d never be here.”

Keep ReadingShow less
Inside the Hitchcock estate after one year on the market

Opulent furnishings and decoration ranging from Asian statues and paintings to Gulf Oil gas station signs adorn the mansion at the Hitchcock Estate.

Photo by Charlie Greenberg

MILLBROOK — After decades of infamy and just over a year on the market, Millbrook’s Hitchcock Estate continues to exist in relative mystery.

After a notorious few years in the 1960s, little has been heard about the estate recently — a stealthy departure from its past. The appearance of last year’s listing provided the first glimpse inside the property in nearly a decade.

Keep ReadingShow less