by William Cocke

Inch by bloody inch, yard by agonizing yard, I wrest the pernicious foe from his resting-place among the rocks and earth. I show the invader no quarter as I yank him up, gather him with others of his kind, and cart him off to be destroyed. All stragglers are eradicated on sight. Exhausted by the brutal campaign, my forearms and hands tremble as I sink to the ground. I can’t rest long, though, as the enemy never sleeps, never ceases his relentless advance. Sound like an excerpt from a long-lost Civil War diary? On the contrary, it’s just another weekend of warfare in my back yard as I battle the invasive species known as Hedera helix, or English ivy.

After habitat loss, invasive species-particularly plants-may be the most serious threat to the survival of native flora and fauna of the southern Appalachians. When the most invasive of these species are introduced-usually as the result of human activities-healthy native ecosystems can be severely compromised, even overwhelmed. Nationwide, more than 4,000 nonnative plant species flourish enough to have become naturalized; about 1,000 of them are considered to be invasive. In the southern Appalachians, that number includes more than 260 species.

Native Americans may have cultivated their own imports such as corn, squash, and beans, but plant species are considered native if they were here before European settlement 500 years ago. Many introduced, or exotic, species are either important agriculturally or pose no threat to natural ecosystems. Some are so ubiquitous that they seem like natives. Queen Anne’s lace is a wild relative of the common carrot and is a European immigrant that escaped from early settlers’ herb gardens and never looked back. Black-eyed Susans were originally native to the Midwest. However, in an example of internal migration, these familiar yellow flowers can be seen in old fields and along roads all over the East Coast, most likely spread west-to-east in the hay and other forage of livestock shipments.

Invasives share a set of aggressive characteristics that allows them to overtake large areas in short order. They use runners or rhizomes to spread their vegetative growth, they produce large numbers of seeds, they use a variety of methods to disperse those seeds, and they have few, if any, natural controls. Some grow so entrenched in the landscape that they become a kind of pollution-biopollution. The worst biopollutants can displace native species entirely, creating a monoculture that leaves little room for biological diversity. They choke out all the competition.

While some invasive species arrived by accident, most were introduced on purpose-either to feed livestock, control soil erosion, or as ornamentals for gardens. If good intentions pave the road to hell, then these offenders are coming up through the cracks and thicketing the shoulders.

Kudzu, for example, sprawls across some seven million acres in the Southeast. This Japanese vine was introduced as an ornamental in the late 19th century, but really spread after the Civilian Conservation Corps used it in the 1930s as a soil stabilizer along roadcuts and in old fields. If left alone, it can smother a forest with vines that can grow as much as a foot per day.

Oriental bittersweet is another vine, originally imported as an ornamental, that looks good in a florist’s display, but is a real killer in the wild. It infests cool Appalachian forestland, girdling trees and shading out other plants. Birds spread its seeds far beyond initial areas of infestation and the plant hybridizes with the less invasive native bittersweet.

The Old World shrub Chinese privet is still a mainstay of the nursery trade and has been planted so extensively as a hedge plant that it seems to be everywhere. It reproduces by seed and underground runners and forms dense stands in the wild that crowd out native species. In the Great Smoky Mountains National Park, its presence in the forest indicates an old homestead site. Park crews spend an average of 550 hours a year in Herculean efforts to control privet through spraying and hand removal.

The invasives’ most-wanted list includes many more offenders, from ground covers and aquatic plants to trees and shrubs. Multiflora rose, purple loosestrife, tree of heaven (or Ailanthus), garlic mustard, princess tree, are just a few of the worst. When these and other species become established in an area, they can be very expensive to control and nearly impossible to eradicate. Overall, invasive plants cost the United States an estimated $34.7 billion per year in agricultural losses and control efforts. Aesthetic intrusions along the 469-mile Blue Ridge Parkway (a particularly vulnerable ribbon of parkland) are harder to calculate, but just as problematic. Who wants to travel a Parkway covered with kudzu or with grove after grove of Ailanthus trees?

Roads are natural vectors for introducing invasive species to otherwise minimally affected forestland (another argument for keeping roadless areas roadless). Earth-moving equipment spreads unwanted seeds, which easily colonize disturbed areas. Hikers are not innocent either, as seeds can hitchhike on muddy boots or clothes. Human activity, it seems, provides an endless variety of means to spread invasive plants. Perhaps we, as a species, are the most invasive of all, affecting the environment in all sorts of negative ways.

Dark, misanthropic thoughts like this tend to take over as I wrestle the English ivy from my yard. Years of neglect from a previous owner have ceded much of it to the invasive ivy and an even more daunting adversary-Japanese honeysuckle. Most of us have fond childhood memories of sipping drops of nectar from the sweet-smelling flowers. But honeysuckle forms ground-smothering mats, overtakes trees, and grows almost year-round. I don’t care if I ever see, or smell, another Japanese honeysuckle again. Unfortunately, despite my sweat and toil, I expect I will. Right now, though, it feels good to rip it out of the ground, and plant a native species in its place. That’s how the battle will be won-one plant at a time.

Charlottesville’s William Cocke is always turning over rocks and rotten logs to see what’s underneath. As a young Boy Scout, he learned that cedar bark makes good tinder and four-of-a-kind beats a full house. He also remembers the Camp-o-ree where he had to kill a live chicken and cook it for dinner. He was not traumatized in the least and has no plans to sue. He can be reached at wtc4q@virginia.edu.