Goats May Quell Weedy Tall WhitetopBy Marcia Wood
July 15, 1998
Hungry goats might help stop the spread of tall whitetop, a weed crowding out native plants in western states. In a preliminary summer grazing test with 13 young goats, the animals ate the white-flowered weed with no ill effects, according to scientists with USDA's Agricultural Research Service. The goat's good health is key because scientists aren't completely certain whether the plant is poisonous to animals.
A combination of tactics--grazing, herbicides, mowing, and seeding with aggressive annual plants--might be needed to thwart the weed. Today's ranchers and other land managers have no fast, easy way to keep it at bay. Cattle and sheep will graze tall whitetop growing amid other plants, but won't tackle pure, dense stands of the weed.
For the grazing experiment, researchers fenced the goats in an infested meadow. The animals grazed thick stands of the weed along with regrowth from those stands and from mowed stands. They ate about 75 percent of the young, tender, more digestible regrowth, compared to about half the vegetation in older stands.
Also known as perennial pepperweed, tall whitetop has cropped up in nearly every western state. It's also well-established in New England. Tall whitetop typically grows from 1 foot to more than 3 feet high--and up to 8 feet tall in wet sites such as along streams, rivers, ditches, irrigation canals and salty marshes.
More details are in the July issue of ARS' Agricultural Research magazine, accessible on the World Wide Web at:
Scientific contacts: James A. Young, USDA-ARS Ecology of Temperate Desert Rangelands Research Unit, 920 Valley Rd., Reno, NV 89512, phone (702) 784-6057, fax (702) 784-1712, firstname.lastname@example.org or Lynn F. James, USDA-ARS Poisonous Plant Research Laboratory, 1150 E. 14 N., Logan, UT 84341, phone (435) 752-2941, fax (435) 753-5681, email@example.com.