Group adds herbicide in Waneta, Lamoka
WANETA, LAMOKA LAKES—The latest rounds of treatment for Waneta and Lamoka Lakes were completed in mid-June.
The state permitted two chemicals to be used to remove an invasive plant called Eurasian watermilfoil and a native plant that was overgrown called Southern naiad. A total of 123.5 acres were included in the plan, paid for by the Lamoka Waneta Lakes Association. This is the third time Waneta Lake was treated to kill the milfoil. Waneta was first treated with a chemical called Sonar in 2003.
Gail Mortimer, pesticide control specialist for the New York State Department of Environmental Conservation, said it contained fluridone. She added that while test results were positive and it was successful in other states, fluridone turned out to be harmful to the native plants. Mortimer explained they could not use a smaller dosage than the manufacturer’s instructions and there was an “adverse effect on native plants.”
However, the invasive plant was still a problem. Mortimer said the state then used Renovate, with the active ingredient of triclopyr, in 2008/2009.
“We were very pleased with the outcome,” she said, adding while it killed most of the milfoil, the chemical left the native plants alone. Mortimer explained that Robert Johnson, manager of Cornell University research ponds, has been analyzing the lakes after the treatments. The Lamoka Waneta Lakes Association also reported that rake tosses dredged up much less weeds after the treatment.
Lakes association representative Dennis Fagan previously said that due to the success, no treatment was needed the following year in 2010. The lakes association said “native plant growth has gone from one extreme (...) to the other extreme of, in some areas, nuisance plant growth in 2008 and particularly 2009.”
“Renovate is very selective in how it works,” Mortimer added.
Renovate was again used in 2012 for the most recent treatment. Mortimer explained the second chemical, Aquathol K, was used to target the native naiad plant. She said Cornell University will continue to monitor the lakes for milfoil plant life. She said the invasive species makes it harder for native plants to survive when it comes into an environment. If a future treatment is needed, Mortimer said it will be done with whatever chemical is recommended at the time. She added weed pulls have been another useful method for getting the milfoil out of the lakes.
Native and invasive plants are not the only things growing in the lake. The New York State Department of Health received a grant to research and do public outreach on blue-green algae blooms and toxins at approximately 90 different lakes. Waneta Lake was one of the lakes the department sampled in 2011. According to the state, algae toxin values collected are expressed as micrograms per liter, also known as parts per billion.
Waneta Lake’s 2011 results ranged from .051 to 2.2037 parts per billion out of six samples. The state explains it doesn’t have a threshold on algae toxicity levels, but advisories elsewhere range from six to 20 parts per billion, with 20 being the most common value. In 2010, SUNY College of Environmental Science and Forestry also collected algae samples and found levels at 41.82 and 98.83 parts per billion.
“Algae blooms are not a new phenomenon, and reports of suspected algae bloom related illnesses are rare,” said Jeffrey Hammond, DOH spokesperson.
The DOH recommends avoiding contact with all dense blue-green algae blooms regardless of measured microcystin concentrations, because other toxins (dermal and/or neurotoxins) may be present, and bloom density and/or toxicity can change rapidly. The department said there are currently no formal guideline levels for microcystin density in New York or the United States as a whole, and the DOH is still investigating published numeric guidance values and other measurable bloom characteristics for their use in issuing recommendations and advisories.