Invasive plant species are a huge problem in modern conservation at our State Parks. These plants can overrun areas and if left unchecked, push out our native species, disrupt natural systems, and negatively impact human activities.
Controlling large infestations is challenging, and sometimes requires using chemical herbicides, which can come with unforeseen costs and undesirable consequences.
But there can be another way that is easier on the environment. To deal with invasive plants at Heckscher State Park on Long Island, we are experimenting with a greener and much cuter alternative – a small army of hungry and quite friendly invasive plant-eating goats.
The goats came from Green Goats, a company from Rhinebeck in Dutchess County that for more than a decade has hired out its goats to combat these invaders at various public parks. Their herd has traveled to seven states, as far away as West Virginia and as close by as Riverside Park and Fort Wadsworth in New York City.
Last year at Heckscher, we released goats into a fenced-in, five-acre site overtaken by an invasive plant called Chinese Silvergrass (Miscanthus sinensis). The goal is for the goats to eat the silvergrass so there will be room for our native plants to again take hold. The goats also have been eating other invasives, including Japanese honeysuckle (Lonicera japonica), common reed (Phragmites australis), and Japanese angelica tree (Aralia elata).
However, since goats will eat pretty much everything, we did not want them to eat the handful of native shrubs left in the enclosure, including eastern baccharis (Baccharis halimifolia), highbush blueberry (Vaccinium corymbosum), and common elder (Sambucus canadensis). So, we put up fences around these native plants to protect them so that when the goats leave, these shrubs will be able to spread into cleared areas.
Last year, we had a bit of a late start and only received the goats in September, but by the end of the growing season in October, we had 70 goats moving and eating through the area. When the goats left for the season, there was significant thinning of the silvergrass and quite a few individual plants were eaten down to the ground. The goats also ate a lot of the Japanese honeysuckle and, surprisingly, killed several angelica trees by eating their bark. The bark and leaves of the angelica tree are covered in many sharp thorns and spines to dissuade herbivores from eating it, but that didn’t stop the goats, who happily stripped the bark right off the invasive trees!
This year, our goats arrived in June and as of this month, we have 61 goats working in the area with more on the way. We have used a drone to fly over the site to track their progress, and expect to do another flight shortly.
A hungry goat can eat up to 25 percent of its body weight each day, said Larry Cihanek, owner of Green Goats with his wife, Ann. An adult goat can weigh between 140 to 180 pounds, so that works out to up to 45 pounds of invasive plants a day. For our herd at Heckscher, that is up to 2,700 pounds of plant invaders being eaten every day!
And the goat “droppings” are a good source of nutrients for the soil as well.
“Using goats like this is like mowing your lawn over and over,” said Cihanek. “You keep the goats on site for a season, and they keep eating as the plants continue trying to regrow. But the goats keep eating the new growth and eventually they starve the roots bit by bit, and the plants will die.”
The Cihaneks now have about 200 goats in their herd, with nearly all the animals being donated by former owners who had been using them for milking, for show purposes, or as pets.
“Eight years is about the maximum for milking, but goats can live for 12 to 14 years. So, this is their second career with us,” he said. “Our goats are living the American Dream: They eat for a living.”
In addition to helping project the environment, the goats are also a good way to draw more people into the park. “In some of our past projects, we have seen that attendance at a park can go up by about 20 percent after the goats come in,” said Cihanek.
Officials at Riverside Park in New York City even held a celebration after the goats finished working there this summer, making the goats the stars of a $1,000-a-ticket fundraiser at a lawn party in August. More than 800 people showed up and there was a contest to vote for the most popular goat, with the winner being Massey, who was presented with a medal and an elaborate bouquet of weeds.
If you would like to see the goats in action, they are staying through October in the eastern section of Heckscher State Park, to the north of the cottages. The Long Island Greenbelt Trail briefly passes a section of the enclosure when it turns westward.
If you see goats with numbered collars, these are the goats that were honored at Riverside Park.
The goats are quite friendly and like being petted. But please, stay outside the fence and do not feed the goats. They are already surrounded by all the food they need!
All photographs by New York State Parks unless otherwise credited.
Post by Yuriy Litvinenko, New York State Parks Regional Biologist for Long Island