This post is written by Tracy Melton, alumnus ('85), donor, and member of the Libraries' Board of Directors.
Recently, several neighbors and I trekked up a narrow, muddy path through dense, jungle-like foliage. Bright, glossy leaves crowned by yellow plumes. Long branches arched above and crowded around. This tropical moment was not faraway and exotic but on College Creek, less than a mile from Colonial Williamsburg.
Those shiny leaves and yellow plumes were on hundreds of mahonia plants growing wild in the forest. Those drooping branches were on hundreds of autumn olives growing on the same small hillsides.
Our group was surveying a ravine on neighborhood common land along College Creek. Scattered invasive species increased in density as we made our way up the ravine, eventually mushrooming into that jungle-like hillside.
That trek caused me to reflect. Over the last couple of years, I’ve been working with neighbors and W&M community members to remove several invasive species from our local environment. The focus has been on autumn olive, mahonia, wineberry, tree of heaven, Japanese honeysuckle, and Japanese stiltgrass. I feel like we’ve done good work and made progress in the areas that we’ve covered.
That moment, though, was a lightening glimpse into the future that our region faces. These invasive species, and others, are proliferating uncontrolled in our natural spaces. Along the east side of South Henry Street, between Cedar Grove and Old Eastern State Hospital Cemeteries, dozens of autumn olives loom like an army of hulking, tentacled War of the Worlds invaders. Between the W&M Law School and Route 199, easily more than a thousand of these invaders have been growing and spreading prolifically.
Mahonia loves our soil, our forests. I’ve seen 3-4 mahonia in yards along a neighborhood street seed more than sixty new ones in the adjacent Matoaka Woods. I’ve seen a couple of mahonia in a landscaped area seed more than 220 in an acre or two of woods. I’ve seen more than 200 mahonia in a similar-size patch of nearby woods. In those first woods, a tall mahonia stood surrounded by forty medium and smaller ones. An invasive thicket from one seed. A mature mahonia produces thousands of seeds.*
Wineberry gained a foothold in the Matoaka Woods, near Monticello Avenue, resulting in a network of patches that totaled probably more than 4000 hard, spiky, red canes. Thick wineberry patches crowd out native species and make it uncomfortable for humans and other species to move through, eventually closing off large areas. Another 2000-cane patch swallowed a stand of pine, cedar, and holly.
Tree of heaven is spreading at Omicron speed. It grows side-by-side with autumn olive along S. Henry Street. It is even popping up in the Colonial Williamsburg parking lot at the southwest corner of Francis and S. Henry Streets. This spring, look along I-64, I-95, and I-295 for tropical-looking trees with smooth, silvery bark and paired, light-colored, long, slender, leaves on branches jutting upward. This summer, look for the yellow and brown and reddish clusters crowded on these trees, holding tens of thousands of seeds. Tree of heaven.
One can observe tree of heaven along these interstates, sometimes in thick patches, all the way to West Virginia, all the way to North Carolina and Northern Virginia. Imagining a journey along these routes, one probably pictures pine, oak, holly, and similar trees sliding by. We may soon picture instead walls of tree of heaven. This might be our Tidewater landscape, our Virginia landscape, our American landscape long into the future.
Tree of heaven overspreads the landscape like a tsunami. It grows in full or dappled light, preferring forest borders but capable of spreading into forests. It allelopathically inhibits the growth of other plants.
Tree of heaven is aggressive and difficult to remove, especially as it may send up numerous shoots in response to the cutting down of one tree. It is foul-smelling (like bad peanut butter) and noxious, perhaps toxic. It is the natural host plant for the catastrophically destructive spotted lanternfly. A neighbor and I carefully removed hundreds of small ones and perhaps a dozen larger ones from a patch of wooded common land approximately the size of a basketball court. The City of Williamsburg successfully eliminated an emerging patch along S. Henry. Tree of heaven can be countered.
Japanese honeysuckle vines strangle trees like a boa constrictor strangles prey. These light-colored, papery vines wrap around trees in precise and elegant loops, like the stripes on a candy cane. The vines use trees to send their canopies toward the sun, eventually killing the tree, leaving their canopies perched atop the snag.
They wrap many thousands of trees in and around Williamsburg. They are plainly visible on local highways and byways. The hundreds of honeysuckle vines draping hundreds of trees near the Bassett Trace Nature Trail trailhead, by Colonial Williamsburg’s Griffin Hotel, provide perhaps the starkest local look at what is happening to our woodlands. It is almost a forest of vines.
Many other plants have migrated from our yards into our forests, where they thrive. I often see Bradford (Callery) pears, mimosas, and wisteria vines driving around the region. Chinese privet (Ligustrum sinense) is another aggressive spreader, two large ones and 60-80 small ones on one small patch of our neighborhood common land. A useful list of invasive plant species in Virginia can be found on the Virginia Department of Conservation & Recreation (DCR) website: https://www.dcr.virginia.gov/natural-heritage/invspinfo.
I’ve lamented thickets of autumn olives, smothering patches of mahonia, wineberry, and tree of heaven, and uncountable honeysuckle vines strangling almost every small and medium deciduous tree on tracts of Williamsburg-area woodlands. But I’ve never felt so overwhelmed as I felt while trekking up that jungle-like path, climbing out of a ravine perfectly typical of the many that cut our landscape. I could envision that jungle pouring down the ravine toward College Creek, flooding the landscape. It is already trickling around my own home.
College Creek still looks much as it did in the sixteenth century when some of the first American encounters between native populations and Europeans occurred along its banks, in these same woodlands. Walking these woods, we can still see and feel see much of what these peoples, and subsequent generations, saw and felt. That is changing in a dramatic and accelerating way.
What can we do? Plant native, remove invasive. Work individually, organize group projects. Lean and teach. Encourage public officials and local businesses and institutions to prioritize the landscape. They are beautiful woodlands, if we can keep them.
*(DCR does not (yet) classify mahonia as an invasive species, although many nearby states classify it as invasive, as do the Piedmont (VA) Master Gardeners. It spreads as aggressively and destructively as any of these other species.)
** Note from Meghan Bryant: Invasive plants are described as such because, unlike "native" plants for any given region, they do not support local species of insects and fauna, which play critical ecological roles. Invasive plants occupy space where native plants could grow instead, and thereby put strain on ecosystems. To learn more, visit "Invasive Plants in Virginia", "Escape of the Invasives", and/or "Why Native Plants Matter." You can also see sources at Swem related to Lonicera japonica, Elaeagnus umbellate, and Ailanthus altissima.