Extreme Makeover

A Look at the Whys and Hows of Ecological Recovery

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Story by April Anderson

Over the past 50 years, humans have changed ecosystems more rapidly and extensively than in any comparable period of time in human history, largely to meet rapidly growing demands for food, fresh water, timber, fiber, and fuel.”
-The Millennium Ecosystem Assessment (MA)

In our area, this change can be seen raging across yards and open spaces in the form of invasive monocultures of greenery. “Leaving things as they are” doesn’t help, as over 270 species of plants classified as “invasive, noxious, pests” are working their way across the Midwest. Considered one of the five major threats to ecosystem integrity by the MA, invasive species demand vigilance and action—carefully timed mechanical, biological, and chemical defenses enable progress in this subtle, but ongoing war against vegetation that threatens the well-being of plants, animals, even humans.

Turf wars

The U.S. Department of Agriculture defines invasive plant species as vegetation introduced to an area that has the ability to produce chemicals that inhibit the growth of other plants, smother surrounding vegetation, and traverse long distances. Competing with native species for water, light, nutrients, and space, invasive species are linked to the decline of 42 percent of America’s endangered and threatened species.

In the Barrington region, this tide is shifting due to the work of informed residents and dedicated volunteers. “A lot of homeowners are cutting down buckthorn to have better views of the rolling hills,” said Citizens for Conservation (CFC) restoration director Tom Vanderpoel. On CFC-managed properties Vanderpoel explained, “All invasive species are on the decline because we kill them.” (Editor’s note: We are sad to report that CFC pioneer Tom Vanderpoel passed away shortly before press time.)

Circling back to the same areas to monitor invasive species each year can enable them to be treated before they get out of control. For biennials such as spring-blooming garlic mustard and summer-blooming sweet clover, stewards strive to remove plants before they go to seed. Purple loosestrife-loving beetles are released into large stands of this invasive wetland plant to keep it from going to seed as the season progresses. Goats are employed in areas with re-sprouting buckthorn and honeysuckle. Native seeds, specially adapted to local conditions, eventually create a thick, impenetrable layer of vegetation to curb future invasions and provide essential habitat, but recovery can take up to a decade.

Impact on wildlife

Invasive species reduce food and shelter for native wildlife. “For pollinators that are physiologically adapted to specialize on particular plants, non-natives may present floral structures that are inaccessible to local pollinating animals,” states the North American Pollinator Protection Campaign.

Dense stands of 14’ high common reed (Phragmites australis) alter hydrological regimes and decrease habitat for migratory waterfowl. Buckthorn roots and honeysuckle change the water chemistry of vernal pools, negatively impacting the development of native amphibians. Honeysuckle leaves break down in water faster than those of native plants reducing the organic matter that provides food and cover for macroinvertebrates.

For robins, raccoons, chipmunks, and other berry eaters, buckthorn and honeysuckle offer unwanted alternatives to native serviceberry and elderberry. Carbohydrate-rich honeysuckle berries lack the nutritional benefits of lipid-rich native fruits, which provide greater energy to sustain migrating birds. Withering and dropping to the ground over the course of winter, seeds from these berries germinate to add more buckthorn and honeysuckle to the region each spring.

Garlic mustard prevents young oak trees from maturing because it inhibits the growth of symbiotic root fungi that oaks need to survive. Ultimately, this invasive plant diminishes nut supplies for squirrels and turkeys, along with a host of the insects that migratory songbirds receive from both oak trees and their associated galls. Blooming about the same time as native toothwort (Dentaria laciniata) each spring, garlic mustard also threatens West Virginia (WV) white butterflies, which lay their eggs on toothwort. Because garlic mustard is more prevalent, WV white butterflies lay their eggs on the invasive rather than the native plant and their caterpillars subsequently perish. Wildlife does not suffer alone.

The toll on humans

Tangled thickets of buckthorn, multiflora rose, and thorn-laden teasel, much like the hostile forest in “The Wizard of Oz”, inhibit access instead of welcoming exploration.

Buckthorn (Rhamnus cathartica) releases allelopathic compounds through leaves, seeds, and roots that alter soil to deter understory and groundcover vegetation, eventually contributing to erosion and diminished water quality.

“While green space clearly has positive impacts on human health, ‘bad’ green space may prove to be detrimental to human health,” says environmental regulatory specialist Hayley Kopelson Effler. He goes on to describe “’bad green space” as areas that are neither traversable nor restorative to mental health. Perceived as unsafe and lacking aesthetics, landscapes ravaged with invasive species discourage positive connections with the natural world.

To add to the perception of danger, wild parsnip (Pastinaca sativa) and giant hogweed (Heracleum mantegazzianum) sap cause burn-like blisters on skin exposed to sunlight. Amur honeysuckle shrubs (Lonicera maackii), which provide habitat for deer, have been linked to increased populations of ticks. Eradicating invasive honeysuckle reduces deer activity as well as ticks, leading some researchers to suggest “management of biological invasions may help ameliorate the burden of vector-borne diseases on human health.”

Shifting paradigms

Removing invasive plants and shrubs that buffer our sacred spaces from the rest of the world take time, planning, and support. Volunteering to assist with local natural areas provides hands-on opportunities to learn about natural areas management and transfer ideas to the home front while improving the ecological health and biodiversity of the community we call “home.”

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Start Your Own Extreme Makeover

Volunteer. Barrington Area Conservation Trust, Citizens for Conservation, Forest Preserves of Cook County, Lake County Forest Preserve District, and Spring Creek Stewards need assistance with restoration work.
Do research. Mechanical, chemical, and biological treatments vary with the habitats and invasive species being addressed. Visit (https://www.niipp.net/) to learn more.
“Do little restorations,” Vanderpoel said. “Kill all the buckthorn and put in 4-5” of mulch. Every 2-3 years, add more mulch. Add native plants.”

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Invasive Plants to Know

Woodland

Garlic mustard (Alliaria petiolata)
First-year basal rosettes of this aggressive biennial remain green through fall and winter, and are one of the earliest plants to sprout new greenery in spring.
Dame’s rocket (Hesperis matronalis)
This showy 4-petaled perennial once added to “wildflower mixes” for spring color overwinters as a rosette.
European buckthorn (Rhamnus cathartica)
Planted as a hedgerow, this invasive is one of the last trees to drop its leaves in fall, and one the first to leaf out in spring, self-seeding from female plants.
Amur honeysuckle (Lonicera maackii)
Once thought to be a valuable shrub to curb erosion and provide habitat, honeysuckle, like buckthorn is one of the last shrubs to drop its leaves and one of the first to green up in spring.
Callery or Bradford pear (Pyrus calleryana)
This thicket-forming tree, planted for its initially compact form and attractive spring blossoms, branches into a tree prone to lose limbs and provide excessive amounts of seed.

Prairie

Teasel (Dipsacus fullonum)
This short-lived perennial (classified by some as a biennial) can be found going to seed right now as rosettes of vegetation cover the soil beneath its prickly browning stems
Sweet clover (Melilotus sp.)
Yellow and white sweet clovers are herbaceous biennials that look like small shrubs their second year. They are full of seed this time of year.

Wetland

Canada thistle (Cirsium arvense)
This noxious, perennial weed has a root system that readily colonizes areas around it. This invasive spends fall storing food for winter.
Reed Canarygrass (Phalaris arundinacea)
This grass has a transparent membrane where blade and sheath meet which distinguishes it from the native bluejoint grass. It is one of the first to add green to spring wetlands.
Common Reed (Phragmites australis)
The roots of common reed can form dense mats over 8’ deep, while clones may persist over 1,000 years. Large plume-like seed heads are an outstanding feature.
Purple loosestrife (Lythrum salicaria)
Introduced for ornamental and medicinal uses, one mature purple loosestrife plant can have up to 30 stems grow from one rootstock and yield 2-3 million seeds.
Narrow leaf cattail (Typha angustifolia)
Cattails invade wetland communities which experience changes in hydrology, salinity, or fertility outcompeting native species to create their own monoculture.