e360 digest


In East Coast Marshes, Goats
Take On a Notorious Invader


By Crystal Gammon

22 October 2014


Over the past 30 years, land managers in the eastern U.S. and Canada have spent countless man-hours and millions of dollars trying to tame a pernicious, invasive reed known as Phragmites australis.
Goats at Freshkills Park
Freshkills Park
Goats eating phragmites in Freshkills Park.
Originally from Europe, phragmites (pronounced “frag-MY-tees”) grows in dense, tall stands that choke off native vegetation and litter wetlands with thick mats of decaying biomass.

Toxic herbicides, controlled burns, and even bulldozers have been the go-to solutions to the problem. But recent research out of Duke University suggests another, less aggressive fix: goats.

Using an experimental wetlands site in Maryland, Brian Silliman, an ecologist with the Duke Marine Lab, found that goats were able to reduce phragmites cover by as much as 80 percent in a matter of weeks. The goats lived on diet of roughly 80 to 90 percent phragmites during the study, and the culling allowed a variety of native plants to gain a foothold, Silliman said.

The idea of using goats for land management has gained momentum in other ecosystems, Silliman said, including in the U.S. South, where goats have helped control invasive kudzu for years. But until recently, Silliman said, “there was a sort of tunnel vision among managers of North American marshes.”

The approach is finding some practical applications — including in New York City, where park administrator Eloise Hirsh deployed a herd of goats at Staten Island’s Freshkills Park, a 2,200-acre landfill reclamation project. In two- to three-week spurts, for a total of roughly 10 weeks, the animals grazed a two-acre section of the marshy park, Hirsh said, after which groundskeepers applied herbicides and then reseeded the area with native marsh grasses. Two years later, according to Hirsh, phragmites remains under control and the test area requires minimal maintenance.

“The goats did what we needed them to do,” she said. “They ate everything.”

Of course, not every situation is suited to these hungry herbivores. Goats, for example, will completely avoid some wetland areas — particularly low-elevation marshes with standing water. And Brian Knox, a supervising forester with Eco-Goats, a vegetation management company in Maryland, noted that goats
Phragmites australis
Matt Lavin/Flickr
Phragmites australis
will not seek out phragmites in an area dominated by other vegetation. In such cases, Knox said, land managers can construct small enclosures to focus the animals on problem areas, moving the fences — and the goats — as the phragmites is consumed.

But that fencing process can be both labor-intensive and expensive, Knox conceded. Depending on the type of land and plant cover, he estimated that using goats to mitigate invasive plants can cost roughly $1,000 to $3,000 per acre. Often, if a plot of land is small — less than a quarter-acre — it’s more cost effective to simply weed by hand, Knox said.

While Freshkills Park officials did not have a cost comparison available, Hirsh estimated that using the goats was significantly less expensive than bringing in bulldozers. She said she hopes to use the technique park-wide in coming years, largely because relying on goats protects the land from heavy equipment and excessive herbicide use.

“Everyone around here needs to get used to the idea of four-footed greenery management,” Hirsh said.




Yale
Yale Environment 360 is
a publication of the
Yale School of Forestry
& Environmental Studies
.

SEARCH e360



Donate to Yale Environment 360
Yale Environment 360 Newsletter


CONNECT


ABOUT

About e360
Contact
Submission Guidelines
Reprints

E360 en Español

Universia partnership
Yale Environment 360 articles are now available in Spanish and Portuguese on Universia, the online educational network.
Visit the site.


DEPARTMENTS

Opinion
Reports
Analysis
Interviews
Forums
e360 Digest
Podcasts
Video Reports

TOPICS

Biodiversity
Business & Innovation
Climate
Energy
Forests
Oceans
Policy & Politics
Pollution & Health
Science & Technology
Sustainability
Urbanization
Water

REGIONS

Antarctica and the Arctic
Africa
Asia
Australia
Central & South America
Europe
Middle East
North America

e360 VIDEO

“video
A look at how acidifying oceans could threaten the Dungeness crab, one of the most valuable fisheries on the U.S. West Coast.
Watch the video.

e360 MOBILE

Mobile
The latest
from Yale
Environment 360
is now available for mobile devices at e360.yale.edu/mobile.

e360 PHOTO ESSAY

“Alaska
An aerial view of why Europe’s per capita carbon emissions are less than 50 percent of those in the U.S.
View the photos.

e360 VIDEO

“Ashaninka
An indigenous tribe’s deadly fight to save its ancestral land in the Amazon rainforest from logging.
Learn more.

e360 VIDEO

Food waste
An e360 video series looks at the staggering amount of food wasted in the U.S. – a problem with major human and environmental costs.
Watch the video.

e360 VIDEO

Choco rainforest Cacao
Residents of the Chocó Rainforest in Ecuador are choosing to plant cacao over logging in an effort to slow deforestation.
Watch the video.

e360 VIDEO

“video
Tribal people and ranchers join together to stop a project that would haul coal across their Montana land.
Watch the video.

OF INTEREST



Yale