NEAH BAY (Sept. 9,2004 — Tansy ragwort is a poisonous daisy look-alike that can kill deer, elk, and livestock. That’s why the Makah Tribe is working to eradicate the non-native weed on tribal lands and private timberlands where deer and elk herds important to the tribe roam.
Tansy ragwort is a well documented threat to livestock. While livestock don’t choose to eat ragwort, it can accidentally get mixed in with hay during harvest. Toxin in the weed kills the animal over time by destroying the liver. Tansy ragwort is native to Europe, but began invading the United States decades ago. Each plant can produce up to 150,000 seeds.
“While it isn’t documented that elk eat tansy ragwort, we don’t know for a fact they don’t eat it,” said Rob McCoy, wildlife biologist for the Makah Tribe. “Domestic cows are fenced in and observed regularly. But when elk die, we don’t always know the cause.” Equally disturbing to wildlife biologists is the proliferation of the invader, replacing native vegetation that elk and deer prefer to eat.
Eliminating the rogue weed requires sweat. The only way to effectively kill the plant is to pull it just before it turns to seed in early summer. “The weed uses a lot of energy to flower, so it can’t re-establish if we pull it now,” said Jon Gallie, wildlife biologist for the Makah Tribe. A moth that kills tansy ragwort is found on the Olympic Peninsula, but not in sufficient numbers to control the prolific weed.
Tansy ragwort pulled recently by wildlife technicians, biologists, and tribal students had root wads up to a few feet in diameter. Thousands of plants were burned, one of the few ways to make sure the plant doesn’t re-seed because seeds remain viable for up to 10 years. Crews pulled weeds on more than 135 acres, both on reservation and, with permission, on Crown Pacific’s private timberlands.
“This will be a multi-year effort,” said McCoy. “The plants live for two years, developing a flower the second year. The flowering plant is easy to find. The first-year plants don’t have flowers and are so small, it’s hard to pull the root. We’ll have to re-visit these areas next year to help keep the tansy population down.”
For more information, contact: Rob McCoy, wildlife biologist, Makah Tribe, (360) 645-3058; Jon Gallie, wildlife biologist, Makah Tribe, (360) 645-3069; Debbie Preston, coastal information officer, Northwest Indian Fisheries Commission, (360) 374-5501