Angora goats help shine spotlight on invasive plant removal

To figure out who does the best job of clearing damaging invasive plant species from the local forest, the Friends of the Wissahickon gives all volunteers a fair shot – even the ones on four legs.

“We wanted to bring more of a spotlight to native and invasive plants, and invasive plant removal,” FOW Outreach Manager Sarah Marley explained of why the conservation group invited six hungry Angora goats to the park.

A few cute and friendly goats snacking on the local shrubbery paints a nice picture, but was there a way to measure the ruminants’ benefits?

Where goats meet science

Under the formal title of the Goat Invasive Control Study (with funding from the Garden Club of America) FOW has taken a scientific approach to utilizing the small goat herd owned by Atglen, Pa. resident Yvonne Post. Can goats have a measurable impact on stubborn invasive plants like knotweed, oriental bittersweet and bamboo, which crowd out native species vital to the ecosystem? How could you keep track? And how could you test the goats’ munching against other methods of plant control, to be sure the program was in the best interest of the park?

FOW set out to answer those questions with a structured, five-year study that began in 2011.

According to a 2011 newsletter, the group identified three 400-square-foot test sites in the Wissahickon woods, with “comparable terrain” and near-total coverage of problem plant species, for annual summer-long studies. Botanists from Bowman’s Hill Wildflower Preserve in New Hope surveyed and documented the plants at each site.

One site received two sprayings of the herbicide glyphosate (also known as Roundup), and another received three hand-clearing sessions from a group of volunteers. The six Angora goats were loosed on the third, for three day-long feasts.

And the winner is…

For the first two years of the study, “we did pit the goats against the humans,” Marley said.

After each treatment on the separate test sites, the botanists surveyed how many invasive plants the three methods had removed.

According to Marley, the results were conclusive: “the humans actually won.”

Post takes a slightly different view, pointing out that her goat herd is small (now reduced to five), and that Angoras are a relatively small breed: a larger group of larger goats might have given the two-legged volunteers more of a run for their money. 

Post also said the goats deserve some credit for enthusiastically clearing a plant that, while it’s actually a native species, most humans won’t touch with a ten-foot pole.

“They love poison ivy,” she said. “The goats ate all the poison ivy [on their test site], and the volunteers wouldn’t even go near it. Goats won hands-down.”

For love of the goats

Post, who in 2005 co-founded Cooking For Real, a nutritional outreach and hands-on cooking education company, lives on an eight-acre former farm near the borders of Lancaster and Chester counties. She has had a soft spot for goats since she adopted her first one about twenty years ago.

“I really like goats, because they’re really interesting animals and they’re very friendly and lovable,” she said, adding that given her interest in responsible agriculture, she “wanted to explore using goats for sustainable weed control.”

She said her goats – each named after a famous artist – are very attached to her, and come when she calls. For up to ten months of the year, the goats happily feed themselves in the brush – one reason generations of farmers, without mowers or herbicides, made sure to keep goats on hand.

The collaboration with FOW isn’t the first time Post’s herd has been of service. They’ve also munched through sites like Longwood Gardens and Media’s Tyler Arboretum. A FOW board member connected with Post through their garden club, and the project grew from there.

Now, the 45-pound goats ride to their sessions in the Wissahickon in the back of Post’s Honda.

Questions welcome

After the experiments of the past two years, “this year we’re really just using [the goats] more as an outreach tool to educate people about native and invasive species,” Marley said.

“If you’re out in the Wissahickon and you see a herd of goats out there, you’re going to wonder why, and you’re going to wander up and ask questions about it,” Marley added. FOW volunteers alongside Post and the goats will answer people’s questions, and talk about ways to aid native plants, like choosing native species for their own gardens.

This year, the goats are tentatively scheduled to make their way along Forbidden Drive on June 23, July 14, and Sept 22 (locals should check the FOW website and Facebook page for confirmation).

Passers-by are encouraged to come pet the goats. Because of their luxuriant mohair coats, “they look like poodles with horns, and they’re very friendly,” Post said.

Post and FOW organizers hope that the furry animals will jump-start interest in helping native plants, without using harmful chemicals.

“It’s a good opportunity for people to see that there are options other than Roundup, or completely shearing things to the ground and hoping for the best,” Post concluded.

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