CLA Says Natural Science is the Best Course for Monitoring Weed Growth

Cornell Scientist Presents Symposiums

August 20, 2008

Mayville, N.Y. -- Cornell University’s aquatic scientist, Robert Johnson, conducted two inter-active symposiums this week for the Chautauqua Lake Association called, “All We Had to Do Was Act Naturally.” He attributed some of this year’s dramatic weed reduction in parts of Chautauqua Lake to a tough trio of hearty insects; a mighty moth, a milfoil-loving weevil and a slender caddis fly.

“Monitoring these insects has shown how they are beneficial for controlling excessive growth of Eurasian watermilfoil in Chautauqua Lake, especially the Burtis Bay area.” Johnson said. “Possibly, the emergent milfoil flowers provided an unusually large area of egg-laying surface for the caddis fly. In 2007, the weevils weakened the milfoil by mining stems. Then, large numbers of the caddis fly finished the milfoil off by ingesting all of the leftover plant material.”

Although it may be hard to believe a trio of insect herbivores played such a significant role in clearing the lake, CLA officials have always had confidence in the scientific approach to controlling the problem. CLA President Tad Wright said, “Bob and his team have worked diligently in coming up with this additional tool to be used in controlling weed growth and we couldn’t be more pleased with the results.”

The symposiums were held at Chautauqua Suites in Mayville and the Casino in Bemus Point. Many lakeside homeowners and Chautauqua Institution dwellers attended the interactive presentations. “I think this event is just wonderful,” Chautauqua Institution resident, Dr. John Khosh said as he peered into a microscope. “Finding out more about the ecosystem of the lake is truly interesting and there should be more of these types of presentations for residents.”

The insects studied and larvae introduced to the lake by Johnson’s team may not have been the only factor that helped clear the lake. According to Johnson, lake levels are much higher this year due to abundant rainfall and this, with cooler spring temperatures has helped hinder overall weed growth.

Johnson said residents can contribute immensely to controlling weed growth by not mowing too close to the shoreline, limiting fertilizers and creating natural buffers like the native plant the water willow . “It’s important for lakeside homeowners to know about simple things they can do to help control future weed growth in the lake. These symposiums help to create awareness about the actions the public can take.”

The CLA wants to continue to be the steward of the lake by supporting a scientific approach. “By keeping accurate historical, scientific data, we can use this information to make prudent lake management decisions in the future,” President Wright said. “The CLA’s main objective is to keep the lake at its natural best.”