[Scientific American, June 28, 2010] Goats aren't known for their refined palettes. They'll eat just about anything green. In places such as Hawaii or the Galápagos, where these grazers are unwanted invaders, this mindless munching has caused major damage. Goats strip away vegetation, which speeds up erosion. In the U.S. West, however, their insatiable appetite has actually been a boon in the fight against invasive species.
Photo: Tammy Dunakin, Rent-a-Ruminant
Tammy Dunakin, chief goat wrangler and owner of Rent-a-Ruminant, LLC, has a herd of about 120 goats on Vashon Island in Puget Sound that she rents out to clear weeds, including invasive species such as Himalayan blackberry, English ivy, Scotch broom and Japanese knotweed. For $725 a day the goats will munch and crunch their way through everything from leafy greens to thorny bramble. The herd can clear an acre in anywhere from six days to two weeks, depending on the density of the brush.
Goats don't have an impact on plant roots, so the weeds will grow back. But if they clip the same area a couple of times a year for a few years in a row, the plants will eventually die, Dunakin says.
What are the advantages of using goats? For one, they're "green". "They're not emitting gas fumes," Dunakin says. Goats are also agile. They can work in areas where it's difficult for people or machines to go. What's more, "they sterilize almost all the weed seed in their rumen so they don't propagate invasives elsewhere," she says. "It's a win–win all the way around."
