In what’s being considered a precedent setting decision, the Adirondack Park Agency (APA) and the Department of Environmental Conservation (DEC) has approved the use of a chemical aquatic herbicide to control Eurasian Water Milfoil in the Adirondack Park. Chemical means of combating aquatic invasive flora have never been allowed in the park prior to now. Although a controversial method of Milfoil control, the Town of Lake Luzerne, just west of Lake George, has been approved to apply 1,560 pounds of the chemical Triclopyr on 11 of the lake’s 111 acres this coming May. The approved Lake Luzerne location site is an area of dense milfoil and is in a relatively secluded area of the lake that has little water flow. During treatment, a sequestering curtain will be placed at the mouth of the treated bay separating the rest of the lake.
As water is obviously one of Adirondack’s most precious resources, the approval of the brand name chemical Renovate OTF has brought up concerns from environmental groups, such as the Adirondack Council who opposes its use. The issues include the fact that Triclopry is designed to target broadleaved dichotic plants such as Milfoil. The chemical does not exclusively target Milfoil, and there is a potential impact on nontarget plants as well as aquatic organisms. In addition, it is slightly toxic to Mallard ducks. The Federal Government warns against using any water treated for any irrigation purposes for 4 months after treatment ends, and swimming is prohibited for 72 hours. Although drinking water is not a concern for Lake Luzerne, as they do not use the lake water for consumption, it would obviously be an issue for other lakes including Upper Saranac Lake.
Triclopyr has been used elsewhere outside the park in the past. Saratoga Lake began treatment in 2008 with mixed results. The need to reapply yearly, as well as the on going use of mechanical harvesters continues.
Although Lake Luzerne feels that this might be their answer to combating the invasive Milfoil problem, there will still be a re-occurring financial and a potential environmental toll. Luzerne has tried the more traditional hand harvesting approach and the use of benthic barriers on the lake bottom similar to Upper Saranac Lake, but was not able to stay ahead of the growing problem. This is something to keep in mind. If Upper Saranac Lake is left unattended for even a short period of time, we may have to revert to more desperate forms of eradication. A one time cost for the 11 acres in Lake Luzerne is estimated between $15,000 and $20,000. Upper Saranac Lake, with a total of 5,000 acres, has an estimated 1,250 acres of potential Milfoil habitat. For Upper Saranac Lake the cost of herbicidal treatment could cost close to 2 million dollars.
The jury is still out on the use of aquatic herbicides. It is something that the Upper Saranac Lake Foundation will keep a close eye on.