High Winds Postpone Herbicide Use On Chautauqua Lake
SOLitude Lake Management was forced to delay herbicide treatment of Chautauqua Lake due to high winds on Wednesdy, and rescheduled the operation for Monday.
The New York State Department of Environmental Conservation has issued permits for the herbicide treatment of 86.4 acres of the lake, including areas of Lakewood, the town of Busti, town of Ellery and village of Bemus Point.
That figure is a large reduction from herbicide treatment last year, which was used to target both curly-leaf pondweed and Eurasian watermilfoil in a 380-acre area. This season marks the first use of the ProcellaCOR, an herbicide with no recreational water use restrictions, to treat watermilfoil only. Six different municipalities combined on herbicide applications for a potential treatment area of over 500 acres.
“I really can’t with any certainty say that it was more or less than what we had expected,” said Vince Horrigan, interim alliance executive director, about the acreage permitted. “The DEC is the one that makes the decisions, and they look at a lot of information. They clearly have the expertise. They were out there on the lake with SOLitude, to my understanding, and I know that especially in the Burtis Bay area there was a lot of pondweed out there. They didn’t find a lot of milfoil, and milfoil is what is being treated this year.”
Curly-leaf pondweed is an invasive species with an early growing season, and large collections of these macrophytes are expected to die off shortly.
Many residents have noted the prevalence of pondweed during the last several weeks, and speculated as to what may have caused the early growth.
“Typically curly-leaf pond weed dies off by the end of June, and of course it can take a week or two,” Horrigan said. “It is a nuisance and invasive species early on. Last year we really had very little of it because it was treated. So there was a lot of disappointment, I think this year that people saw so much of it. But it will die off early on.”
Horrigan said that because of pondweed’s tendency to die off early, it may not have been practical to apply for DEC permits to treat it with herbicides.
“By the time we would get permits, and by the time we would actually start to treat it, it is already dying off,” Horrigan said. “My observation, today (Tuesday), is we are starting to see that happen.”
Third-party monitor Princeton Hydro will be taking pre- and post-treatment data to help determine the effectiveness of herbicides this year, while the CLA crews continue to harvest nuisance weeds, given weather conditions this spring.
One of the crucial areas of lake maintenance research is to better understand the relationship between nuisance weed growth and decay, the nutrient profile of the lake, and harmful algael blooms.
Weeds that die off and fall to the lake bottom can produce nutrients like phosphorus, which play a role in the growth of algae.
“When they harvest pondweed they will typically cut it below the water surface and they will collect what they cut. That helps to reduce some of the biomass,” said Randall Perry, alliance project manager. “That is something that I know folks around here are very interested in understanding is, how does pondweed cycle the nutrients, milfoil cycle the nutrients, how do each of the major plant types do that? Those are all really important questions and that is why data collection is so important.”
At a Lakewood meeting this week, related questions were discussed.
“The question of whether or not the herbicide treatment last year has caused worse conditions with the curly leaf pondweed is a valid question to ask,” said John Jablonski, executive director of the Chautauqua Watershed Conservancy. “We have a lot of abundant nutrients in the sediments and in the water column. If you take one element of the ecosystem out something comes in to replace it. Either different plants or algae. So I think that is a question that needs a good answer before herbicides are used on a large basis again like they were last year.”
According to a pondweed factsheet issued by the Minnesota Department of Natural Resources, “Curly leaf may grow to problem levels in a lake one year, but not the next. This appears to be due to the weather, which can cause variations from year to year in environmental conditions in lakes. Problems caused by curly leaf can be managed using available methods of control. Dense mats of curly leaf that interfere with use of a lake can be reduced bymechanical harvesting or treatment with herbicide.”