Capital Press

The U.S. Bureau of Land Management wants to expand its arsenal of pesticides to fight noxious weeds in Oregon.

On Oct. 2, the agency released a draft environmental impact statement that examines the potential effects of using up to 14 additional herbicides in the state.

Canada thistle, Russian knapweed and other invaders could be controlled with safer and more target-specific chemicals developed in the past two decades, said Todd Thompson, project manager for the BLM.

Currently, the agency is limited to using four herbicides -- glyphosate, dicamba, picloram and 2,4-D -- as part of a 1987 court decision that only pertains to Oregon.

"If herbicide resistance was to develop, we would have another tool for treatment," said Thompson.

Noxious weeds invade more than 140,000 acres of BLM land per year in Oregon, crowding out native plants, damaging wildlife habitat and contributing to wildfires, according to the environmental impact statement.

Of the 15.7 million acres of BLM land in the state, about 1.2 million are already infested with such weeds to some degree, the statement said.

However, in 1984, a federal district court judge ruled that BLM hadn't properly analyzed the effects of pesticides on human health and barred the agency from using any chemicals to suppress weeds.

That order was modified three years later to exclude the four above-mentioned herbicides, after the agency had completed an environmental impact statement.

The latest draft environmental impact statement is the BLM's first step toward expanding the list of approved pesticides. The statement is now up for public comment, after which a final version and record of decision will be published.

The decision would still be subject to administrative appeal, after which a judge from the U.S. District Court for Oregon would need to lift the injunction on the additional pesticides.

"We've got a step or two left to go," said Thompson.

The BLM has been cooperating with the environmental group that filed the initial lawsuit -- Northwest Coalition for Alternatives to Pesticides -- but it could still encounter resistance to the plan from other organizations, he said.

"There may new challenges to the program that surface," Thompson said.

The Northwest Coalition for Alternatives to Pesticides declined to comment on the matter and referred questions to Umpqua Watersheds, another environmental group.

Francis Etherington, conservation coordinator for the Umpqua Watersheds, said the group is still reviewing the draft environmental impact statement, but would likely be displeased with any program that increases pesticide use.

The group wants to see if BLM's plan includes provisions to prevent the introduction of invasive weeds without using chemicals, she said.

BLM lands in Oregon are unique because they're often interspersed with private lands in a "checkerboard" pattern, which could lead to higher human pesticide exposure -- particularly in regard to drinking water, Etherington said.

"There's a lot more people's backyards that will be affected by this," she said.

Possible tools

Additional herbicides considered for use on Oregon BLM lands: bromacil, chlorsulfuron, clopyralid, diflufenzopyr, diquat, diuron, fluridone, hexazinone, imazapic, imazapyr, metsulfuron methyl, sulfometuron methyl, tebuthiuron and triclopyr.

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