Milfoil-Munching Weevils Planned for Lake Pend Oreille
Local groups seeking alternatives to herbicides to control milfoil are promoting a biological control project.
Local groups seeking alternatives to herbicides to control milfoil are promoting a biological control project using the milfoil weevil.
Partners for Milfoil Control has secured $90,000 toward the project and needs another $85,000 to fully fund it.
“We see this as a great opportunity to investigate non-herbicide control milfoil in our lake, while contributing to the body of research on weevils as a control method,” said Diane Williams, executive director of the non-profit Tri-State Water Quality Council, fiscal agent for the project.
Other partners in the effort include Panhandle Environmental League, Selkirk Conservation Alliance, Sandpoint Mothers for Safe Water and the Idaho Conservation League.
Three of the partner groups serve on the Bonner County Aquatic Invasive Species Task Force, a diverse county advisory board that sought state funding unsuccessfully in 2007 to purchase and study weevils as a control method.
Over the past three years, more than $5 million of taxpayer money has been spent in unsuccessful attempts to eradicate Eurasian water milfoil in Lake Pend Oreille and Priest Lake. Most of the money has been spent on herbicides. Results from this year’s treatment of about 2,100 acres of milfoil are still uncertain.
“In these times, we need to be careful about how we spend every penny,” said Heather Lewis Sebring of Sandpoint Mothers for Safe Water. “Yet, millions of dollars are being spent on herbicides that are not succeeding in eradicating milfoil. It raises budgetary and health concerns about the long term consequences of using herbicides year after year.”’
Weevils have been used for more than a decade in the East and the Midwest with some success. The weevil does not eliminate milfoil, but feeds on and burrows into the milfoil stems, killing and stunting the weed’s growth, controlling its spread and giving native aquatic plants a chance to reestablish.
Lake Pend Oreille already has a native milfoil weevil in low densities. The proposed project would involve collecting native weevils and producing thousands of them in a culturing facility, stocking them in beds of milfoil in Lake Pend Oreille, and studying the results. The demonstration project would contribute to on-the-ground knowledge about non-chemical treatments that can be used locally and in other waterways.
The Tri-State Water Quality Council recently concluded a two-year demonstration project using bottom barriers in Bottle Bay that led to the Idaho Department of Lands establishing a permitting procedure for private landowners to use bottom barriers for aquatic weed control around their docks.
The weevil project would begin in 2009 if adequate funds can be raised in time. The project got a head start with a $25,000 grant from the Sangham Foundation, a private conservation-oriented foundation with ties to Bonner County.
“We’re already half-way there,” Sebring said. “If everyone in Bonner County bought two weevils at $1 each, we’d have enough to get started in the summer of 2009.”
For more information, or to make a tax-deductible donation, visit www.tristatecouncil.org or call 208-265-9092.