US:Eugene seeks public comment on herbicides to fight invasive weeds

Date:07-07-2011

After 27 years of fighting invasive weeds without the high-powered help of toxic chemicals, the Eugene district of the U.S. Bureau of Land Management wants to add herbicides back into the toolkit.

Eugene district BLM officials are inviting public comment on the agency’s proposal to use four herbicides to kill weeds along roadsides and in rights of way, but not on recently harvested timberlands or to improve livestock forage areas.

The agency is looking for constructive comments rather than a simple “spray” or “don’t spray” response, district spokesman Michael Mascari said.

“Alternatives we haven’t thought about or a suggestion on buffers,” for example, Mascari said.

Herbicide use will be limited, Mascari said. Of the 1,500 acres on the Eugene district that are mowed or where weeds are hand-pulled annually, herbicides are being proposed for use on between 100 and 500 acres, Mascari said. The BLM oversees 315,000 acres in the Eugene district and estimates that about 18,000 are infested with noxious weeds.

The BLM stopped using herbicides in Oregon in 1984 after a court injunction in response to a lawsuit filed by the Eugene nonprofit conservation group Northwest Coalition for Alternatives to Pesticides.

The coalition had argued that the agency had not followed federal procedures in approving the use of herbicides on public lands, and a judge agreed.

The BLM eventually wrote an environmental impact statement on its proposal to use herbicides, but a final management plan wasn’t completed until last year.

That management plan permits the agency to use 17 different herbicides to control weeds but only in limited circumstances.

Now individual districts, including Eugene, are developing site-specific proposals for using chemicals.

Locally, four herbicides are under consideration. Glyphosate, imazapyr, triclopyr and clopyralid are effective on a range of plants, from woody brush to grasses and broad-leaved perennials.

The BLM wants to use them on particularly troublesome invasives such as Scotch broom, knapweed and false brome.

The herbicides can only be used on plants that have been officially designated on county, state and federal lists as noxious weeds, according to agency documents.

The Northwest Coalition for Alternatives to Pesticides won’t be submitting comments on the new proposal, Executive Director Kim Leval said. The coalition is more focused these days on helping farmers find alternatives to pesticides and on working to keep pesticides out of schools, she said.

The coalition considers it a victory that the BLM isn’t proposing to use herbicides in support of logging on the millions of acres of forests that it manages in Oregon, Leval said.

Another conservation group, the Oregon Toxics Alliance, will be submitting comments, said Executive Director Lisa Arkin.

Herbicides do damage not just to the weeds they target but to native species as well, she said.

Long-term herbicide use will create weeds less susceptible to their effects while harming less hardy natives, Arkin said.

Because BLM lands are broken up into one-square-mile holdings that are interspersed with private lands, the federal property is close to towns, farms and homes, Arkin said.

The new herbicide policy could harm those who live nearby and who earn their living from organic farming, she said. Those who use BLM lands for hunting or mushroom gathering also could be at risk, she said.

The BLM said it will only be doing ground application and not spraying herbicides by helicopter or plane.

The deadline for commenting on the issue is July 16.

Possible products

The BLM proposes using these chemicals

Glyphosate: Widely used to control grasses, sedges, broad-leaved weeds and woody plants. Not a carcinogen. Toxicity to fish ranges from low to high, depending on brand.

Imazapyr: Used on perennial grasses, broad-leaved herbs, woody species, riparian and emergent aquatic species. Not a carcinogen. Not known to harm fish.

Triclopyr: Highly effective on woody plants. Carcinogen status unknown. Can move through the soil to groundwater, ranges from nontoxic to highly toxic to fish.

Clopyralid: Controls broad-leaved perennials. Carcinogen status unknown. Interferes with animal reproduction in lab tests.