LAKE COUNTY — The California Department of Food and Agriculture (CDFA) plans to spray copper on the water early next week around the perimeter of a four-acre bed of tulles approximately one and a half miles west of Clear Lake State Park to keep a mass of the invasive aquatic hydrilla weed found there from spreading while authorities decide how big a problem they have and how to treat it, according to officials.
The hydrilla weeds growing among the tulles were the first major find of the invasive plant this year, according to Patrick Akers, the supervising scientist over the California Department of Food and Agriculture (CDFA) Aquatic Plants Eradication Program. He is coming to Lake County from Sacramento Tuesday, in part to help decide how to get rid of the weeds.
“We need to get a clear sense of how much hydrilla is back in there, and in areas where we do find it, we will treat it with Sonar,” Akers said.
Sonar is the trade name for fluridone, one of two herbicides used to combat the weeds. It comes in the form of pellets, and Akers said CDFA boat crews may have to use backpack sprayers modified to shoot the pellets 50 to 60 feet into the dense tulle patch.
“We have never really dealt with a situation where we have hydrilla so far back in a tulle bed,” Akers said.
CDFA Agricultural Technician Russ Huber said Wednesday that hydrilla was spotted at least 40 feet into the swathe of tulles from the west end of the patch, and the plants were found on the eastern end the next day.
Application of Sonar and a copper compound called Komeen, which kills the plants on contact, stopped in 2006 for the first time since the CDFA began fighting the aquatic weed on Clear Lake in 1994. This summer marks the second growing season the invasive weeds were found in Clear Lake since then.
“The protocol is to treat until you find zero plants, then for three more (years) without finding any more plants. Then you monitor for another three years before you even consider declaring eradication,” Akers said.
The cycle started all over in 2007, meaning the CDFA will be treating on Clear Lake for a minimum of six more years, according to Akers.
The hydrilla is a fast-growing, non-native aquatic weed that drives out other aquatic plants as it forms mats that can cover entire water bodies.
Contact Tiffany Revelle at trevelle@reccord-bee.com.
