Invasive plants got your goat?
Enjoy a field tour to learn how using goats for invasive plant control can help restore native ecosystems.
As spring begins awakening across Michigan, people begin longing for a walk through the woods or fields to enjoy fresh air, spring wildflowers, and the music of returning songbirds. In many locations, the first green we see isn’t all that welcome. Many nonnative, invasive shrubs including glossy buckthorn, multiflora rose, bush honeysuckles, and autumn olive get a jump on leafing out in the spring. This evolutionary advantage paired with rapid, spreading growth often means that native shrubs and other vegetative species are crowded out from many of our natural areas. These widespread invasions result in a continued loss of biodiversity and wildlife habitat.
Once invasive plants are well established, efforts to eradicate—or at least control—these invaders are expensive and time consuming. Conventional approaches include mechanical or hand-pulling, or cuttings that often require a follow up application of chemical herbicides to prevent sprouting. An alternative way to get a foothold on invasive species control is through controlled livestock grazing. Using goats are common choices because they’re easier to transport to different areas and are generalists when it comes to foraging.
Jared Harmon, the executive director of the Mid Michigan Land Conservancy, will be bringing a few of his goats to begin controlling an overabundance of honeysuckle, buckthorn and autumn olive on portions of the Michigan Wildlife Conservancy’s (MWC) Bengel Wildlife Center in Bath, MI. Jared answered a few commonly asked questions about using goats for this purpose:
Q: The old saying is that goats eat everything. Is this true?
Jared: “They’re pickier than you might think. They’ll turn up their noses at some kinds of hay varieties, for example. They generally prefer shrubs and vines, and really like oriental bittersweet, autumn olive, buckthorn species, and even poison ivy. Grasses are least favored, but that is not as healthy for them anyway.”
Q: Are there plants they definitely should not eat—from a goat health perspective?
Jared: “Things to look out for are black cherry, bittersweet nightshade, red maple, black and pale swallowworts, poison hemlock, and rhododendrons, as they are poisonous for goats. It’s also a good idea to avoid oaks because of the tannins they produce.”
Q: What are the biggest benefits of using goats for invasive plant control?
Jared: “They can navigate steep slopes or other hard-to-reach areas a lot easier than people or machines, with a lower overall impact on the land. Plus, their manure doesn’t smell as bad as other livestock, which is another perk of using goats for these control methods.”
Q: When is the best time in the season to introduce goats for invasive control?
Jared: “I usually get them started after the spring flush, so generally May, and all the way through the fall. It depends on the weather, but even late fall can work because invasives like buckthorn, honeysuckle, and autumn olive often still have their leaves.”
Q: When birds eat fruits from invasive shrubs like buckthorns and honeysuckles, they end up depositing the seeds in their droppings. These seeds then easily germinate in new locations. Will goats be doing the same thing—sowing seeds as they are being ‘hired’ to knock back invasives?
Jared: “Their four chambered stomach destroys about 99% of seeds they end up eating, so the risk of spreading seeds from their manure is pretty low.”
Q: Do areas need repeated grazing cycles to be effective? What else might land managers need to do for effective invasive control?
Jared: “If you’re not using herbicides to follow up after the goats, then yes, grazing will need to be repeated. Even if you bring in goats just once, though, it lowers the amount of herbicide you’ll need to use later.”
Q: Is there anything else that people should watch out for if they want to use goats for invasive plant control?
Jared: “Definitely avoid using them in areas with rare or endangered species, because they will eat everything that they can reach when they’re out there.”
Prescribed Goat Grazing Event
Jared and the MWC’s director of wildlife programs, Drew Monks, will be offering a presentation and demonstration of the goats’ work on Sunday, April 21, from 1-3 p.m. Anyone can register for this free event.
This event is being co-hosted with Michigan State University Extension, the Mid Michigan Land Conservancy, Michigan Wildlife Conservancy, and the Michigan Forest Association.