Minnesota, Wisconsin conservation officials try to get jump on worms
Invasive, nonnative species wreaks havoc with gardens, forests
ST. PAUL, Minn. (WKBT) — Forget about the British invaders’ “Jumpin’ Jack Flash,” because jumpin’ worms are the invasion to fret about these days, according to conservationists in Minnesota and Wisconsin.
Although the worms muscled into Minnesota in limited numbers in the Twin Cities and Rochester area in 2006, the state’s Department of Natural Resources issued a warning this week about an increasing threat from the worms and their environmental pillaging.
“I never imagined an invasive species as horrific as these jumping worms,” forestry expert Lee Frelich says in a video the DNR posted for the alert.
“When I saw the first forest that was infested … just from a person walking, the soil slides down the slope,” says Frelich, director of the University of Minnesota Center for Forest Ecology.
“So plants can’t get rooted in it. And if the plants are destroyed, the whole plant pollinator network goes down — and that’s the base of the whole ecosystem,” he says.
The pesky pariahs were introduced accidentally into the southeast United States in the 19th Century.
Of course, like any invasive species, the worms — also known as Asian jumping worms, crazy worms, Alabama jumpers and snake worms — don’t respect state boundaries. They leaped into Wisconsin in 2013, when the species from the genus Amynthas was confirmed at the University of Wisconsin-Madison Arboretum.
“Native to eastern Asia, they present challenges to homeowners, gardeners and forest managers,” according to the Wisconsin DNR jumping worm website, a collaborative effort with the UWM Arboretum, the University of Wisconsin-Extension and the Olbrich Botanical Gardens.
“Jumping worms get their name from their behavior. When handled, they violently thrash, spring into the air and can even shed their tails to escape,” the website says.
“Jumping worms feed ravenously on organic matter in soil, leaf litter and mulch and excrete grainy-looking, hard little pellets that alter the texture and composition of soil,” the site says.
The worms not only consume nutrients that plants, animals, fungi and bacteria need to survive but also leave soil that resembles large coffee grounds. The soil provides poor structure and support for many plants, according to the Wisconsin website.
Damage isn’t limited to the ravages of jumping worms, say officials of the Badger State and Gopher State DNRs. All earthworms can harm forests.
“Earthworms change the environment to suit their needs,” says Brad Herrick, ecologist and research program manager at the UWM Arboretum. “When they are introduced, they make a host of physical, chemical and biological changes to the soil environment.”
However, jumping worms are especially diabolical, in part because they are highly competitive with other species and grow rapidly, Herrick is quoted as saying in the Midwest Messenger reporter.
Also, unlike the common Lumbricus terrestris — or European earthworm, aka night crawler — jumping worms hunker down in the soil’s top section and they don’t create tunnels that roots then can use as they grow. They reproduce faster than rabbits, and they grow rapidly, which means they consume more nutrients.
In short, their gluttonous ways starve other invertebrates, and they leave a hostile environment for plants. Instead of leaving behind nutrient-rich castings that nurture the soil, they morph the ground into soft, dry soil pellets on the surface that rain erodes easily.
The result is bad for crops but good for weeds.
People inadvertently spread the worms throughout North America by moving potted plants, soil, compost, mulch and fishing bait, ecologists say.
Jumpin’ worms don’t make good bait because anglers find the things impossible to hold onto — let alone thread on a hook, with their wild gyrations.
Most earthworms, including popular baits such as night crawlers and red wigglers, can damage soil, so DNR experts advise that anglers throw leftovers in the trash instead of tossing them into the water or onto the ground.
Eradicating the jumpers is difficult, if not impossible, ecologists say.
“There is no ‘magic bullet’ to control jumping worms, at least not yet. Management mainly consists of taking precautions to not move them onto your property. If they are already there, you will need to adapt and adjust until there are better control options available,” the Wisconsin jumping worm website says.
In Minnesota, jumping worms are classified as unlisted nonnative species and cannot be introduced legally into the environment, the state’s DNR website says.
Indeed, the Minnesota DNR is mulling listing the worms as a prohibited invasive species, which would make it a misdemeanor to possess, import, buy, transport or introduce jumping worms without a permit.
Meanwhile, state officials have a BOLO out on the jumpers.
Laura Van Riper, terrestrial invasive species coordinator for the Minnesota DNR, told the Minneapolis Star Tribune, “We need gardeners and anglers to be vigilant and to contact the DNR when they think they’ve found jumping worms.”
COPYRIGHT 2020 BY WKBT/News8000.com. ALL RIGHTS RESERVED. THIS MATERIAL MAY NOT BE PUBLISHED, BROADCAST, REWRITTEN OR REDISTRIBUTED.