It’s finally spring and your attention may be turning to sprucing up or creating green spaces around your home, school or business.
But be careful when choosing flowers, shrubs and trees to plant. You could unknowingly introduce an invasive plant into the surrounding environment. Sometimes, a plant in your yard can become an invasive menace in the wild.
Plants are considered invasive if they spread out of control, dominating the local environment and crowding out native plants. Because these plants have been introduced into an environment in which they did not evolve, there are no natural predators, parasites or other controls to keep them in check.
Invasive plants share a few common qualities that make them a threat to the natural areas. They spread aggressively by runners or rhizomes. They also produce large numbers of seed that survive to germinate and disperse from the parent plant through a variety of methods including wind, water, wildlife and people. The majority of invasive plants are also nonnative. Native plants are generally recognized as those occurring on this continent prior to European settlement.
Invasive plants are problematic because they outcompete native plants for light, water and nutrients, sometimes eliminating entire native plant communities. This changes the composition of the landscape, and the ecological balance of plants, animals, soil and water achieved over many thousands of years is destroyed.
When invasive plants take over wetlands, forests or meadows, we lose the native plants and the habitats and animals that rely on these species for food and shelter decline.
Invasive plants also affect the recreational activities that we enjoy in natural areas such as boating, birding, fishing and exploring. Some invasive plants become so thick that it is impossible to access waterways, forests and other areas.
Estimates indicate that nonnative plants infest 4,600 new acres of federal land each day. Overall, invasive plants threaten every aspect of the North American environment including National Wildlife Refuges, National Parks, recreation areas, wilderness areas, forests, wetlands and croplands.
Approximately 4,000 species of nonnative plants have established free-living populations in the United States. Of these, more than 1,000 nonnative plants have been identified as a threat to our native plants and wildlife.
Invasive plants and animals costs the U.S. hundreds of billions of dollars each to control on agricultural and recreational lands.
How you can help? First, be careful when choosing plants. If you know you have invasive plants on your property, consider removing them and replacing them with native species. Here are few troublesome plants to avoid and some alternative native plant choices.
- Instead of purple loosestrife (Lythrum salicaria), plant these natives: blazing star (Liatris spicata), New York ironweed (Vernonia noveboracensis), obedient plant (Physostegia virginiana), Joe Pye weed (Eupatorium dubium)
- Instead of common daylily (Hemerocallis fulva), plant these natives: wood lily (Lilium philadelphicum), Canada lily (Lilium canadense), ox-eye sunflower (Heliopsis helianthoides)
- Instead of Chinese wisteria (Wisteria sinensis) and Japanese wisteria (Wisteria floribunda), plant these natives: American wisteria (Wisteria fructescens), trumpet creeper (Campsis radicans), trumpet honeysuckle (Lonicera sempervirens)
- Instead of English ivy (Hedera helix) and Japanese pachysandra (Pachysandra terminalis), plant these natives: alum root (Heuchera americana), white wood aster (Eurybia divaricata), foam flower (Tiarella cordifolia), partridgeberry (Mitchella repens)
- Instead of winged burning bush (Euonymous alata) and Japanese barberry (Berberia thunbergii), plant these natives: red chokeberry (Aronia arbutifolia), Virginia sweetspire (Itea virginica), highbush blueberry (Vaccinium corymbosum)
- Instead of tree of heaven (Ailanthus altissima), plant these natives: staghorn sumac (Rhus typhina), ash (Fraxinus pennsylvanica or americana), black walnut (Juglans nigra)
- Instead of Bradford pear (Pyrus calleryana ‘Bradford’), plant these natives: redbud (Cercis canadensis), serviceberry (Amelanchier canadensis), southern arrowwood (Viburnum dentatum), flowering dogwood (Cornus florida
Native Plant Resources
- Download a copy of Plant Invaders of Mid-Atlantic Natural Areas. The color guide describes many more common invasive plants and suggests alternative native plants to use in their place.
- Visit the Plant Conservation Alliance’s Weeds Gone Wild website or the USDA’s National Invasive Species Information Center.
- Contact your state native plant society for information about native plant alternatives to invasive plants.
- Contact your state Cooperative Extension Service for more information about controlling invasive plants.