West Virginia’s worst invasive plants & what to do about them

CLARKSBURG, W.Va. (WBOY) — With summer in full swing, so is travel and yard work season. West Virginia is known as a “Wild and Wonderful” state, and many residents care about keeping it that way. Here are some simple things you can do to curb the spread of invasive plants in the Mountain State.

But First: What Makes a Plant Invasive?

Invasive plants are defined as plants that are not native to an area and that have a detrimental impact on the ecosystem they are invading. Some plants, while not native to West Virginia, grow very quickly in West Virginia, making it difficult for native species to get adequate nutrition or space to grow. Oftentimes, there are no local animals that eat invasive species, worsening the overgrowth problem and posing a new one: Starving native animals if the invasive plant becomes too prominent in the ecosystem.

What Plants Should I Look Out For?

While there are dozens to hundreds of invasive plants in West Virginia, Natural Heritage Botanist John Burkhart, who works out of the West Virginia Division of Natural Resources’ (DNR) Elkins office, said there are a handful of emerging invasive species to look out for while you’re traveling or maintaining your property this summer.

Burkhart said some of the plants at the top of his mind now are Japanese stiltgrass (Microstegium vimineum), autumn-olive (Elaeagnus umbellata) and bush honeysuckle like Morrow’s honeysuckle, Tatarian honeysuckle and Amur honeysuckle (Lonicera morrowii, Lonicera tatarica and Lonicera maackii).

The Amur and Morrow bush honeysuckles have white flowers that turn yellow with age and the Tatarian honeysuckle has pink flowers. Berries range from red to orange, and are occasionally yellow, and are eaten and dispersed by birds. They usually grow in abandoned fields, roadsides, woodlands and edges of marshes, but Morrow’s honeysuckle can also grow in bogs, fens, lakeshores and other uncommon habitats, according to the United States Department of Agriculture (USDA).

Native birds spread bush honeysuckles, but are also especially at risk from the plant because its berries contain mostly carbohydrates when birds need high-fat, nutrient-rich food for adequate nutrition for long flights.

Japanese stiltgrass is an annual grass that has a shiny midrib on its upper surface, distinguishing it from native grasses. It grows near moist forests, near wetlands and on roadsides, according to the USDA. It’s usually spread by mowing, tilling, foot traffic and flooding but deer can also spread the seeds on their hooves and fur. Burkhart said you can do your part to keep this particularly invasive plant from spreading by cleaning off the bottom of your boots and washing clothes after outdoor excursions.

Autumn-olive is another species Burkhart said he’s particularly concerned about. The USDA says this fast-growing shrub can grow up to 20 feet tall and has light yellow flowers with a strong smell and grows large amounts of small, round, red fruits that birds love to eat, but they also have low nutrient contents. Burkhart said bird droppings are the main source of its spread through West Virginia. The USDA warns these shrubs can grow in nutrient-bare soil and outcompete native plants.

Burkhart also pointed to two species of plants that are becoming an issue, but that are still available for purchase at some nurseries throughout the state. If you see them for sale, Burkhart stressed you should not buy them: The Callery or Bradford pear (Pyrus callereyana) and the Japanese spiraea (Spiraea japonica).

Some other invasive species that Burkhart said are becoming a concern include Japanese knotweed (Polygonum cuspidatum), multiflora rose (Rosa multiflora) and fig buttercup (Ficaria verna).

Japanese knotweed (Polygonum cuspidatum) usually grows in riparian areas, or the area near the water in wetlands. These shrub-like herbs grow and spread quickly and can negatively affect water quality and fish habitat, all while failing to stabilize stream banks like native plants do, according to the USDA. Its small flowers are a green-tinted white color and its seeds are dispersed through the wind, so they could cling to clothing.

The multiflora rose (Rosa multiflora), also known as the baby rose, Japanese rose, seven-sisters rose, rambler rose and multiflowered rose, is originally from Eastern Asia, but was cultivated for ornamental, erosion control and natural fencing purposes since the plant forms dense thickets, but the USDA says those traits mean the plant invades pastures, crowding out native species. The fig buttercup (Ficaria verna), or lesser celandine, poses the same problem.

Are There Any Resources to Identify Invasive Plants With?

The USDA has a pamphlet that includes information about invasive plants in the area. Click here to see it.

Burkhart also recommended the Seek app by iNaturalist, which is available in the Google Play store and the App Store, to identify plants, saying it’s usually surprisingly accurate.

Burkhart said at the moment, the state doesn’t have a method to report an invasive species sighting to the DNR, but it’s something he’s interested in looking into.

So What Should I Do if I Spot an Invasive Plant?

If you spot one while you’re out hiking, fishing, hunting or enjoying any other outdoor activity, make an extra effort to clean off your shoes and clothes so that no seeds hitch a ride home with you or to your next destination. Luckily, Burkhart said human activity is generally only a concern with invasive grasses, not bushes, as long as you avoid buying and planting invasive shrubs and trees.

If an invasive species has made its way onto your property, you’re in for more work. Burkhart said the best way to handle an invasive species on your property is with a mixture of mechanical control—weeding, mowing, pruning or cutting down the plant—and chemical control, or herbicides. Burkhart recommends buying small amounts of the pre-mixed herbicides on this USDA list and using them as directed on the plant.

Burkhart said you’ll likely need to consistently use a combination of mechanical control and chemical control for four to five years in a row to keep an infestation of an invasive species from returning.