An invasive plant is a non-native plant that has "escaped" cultivation and spreads aggressively. Invasive plants choke out other plants. As a further insult, they require more water, fertilizer and care than other plants. Some invasives, like Kentucky bluegrass and winter creeper, are invited guests. Others, like dandelions and sweetclover, were spread by grazing animals or their own prolific seed production. Whenever possible, choose native plant alternatives for your landscape.
Reduce the time and expense of spraying, pruning and watering non-native species not suited to your area. Norway maple, tree of heaven (Chinese sumac), Australian (whistling) pine, weeping willow and black locust are just some of the trees listed by the U.S. Forest Service as potentially invasive. Winged burning bush, Japanese barberry, summer cypress (kochia scoparia) and wisterias are sold in nursery centers but are also invasive. Plant sugar maples instead of Amur maples; yellow or river birches instead of European white birch; the native varieties will grow better and be more pest and disease-resistant.
"Native Alternatives to Invasive Plants; a Brooklyn Botanic Garden All-Region Guide" lists regional alternatives. For the South, choose American smoke tree, witch hazels, magnolias, sweet gum, silky camellia, Southern catalpa, sand pine, cottonwoods and honey locusts. Virginia live oak, chinquapin, water oak and willow oak are native oaks.
Northern natives include Kentucky coffee tree, swamp white oak, American mountain ash, Northern red oak, black cherry, black willow, quaking aspen, sugar maple, redosier dogwood and highbush blueberry. Osage orange, big-leaf maple, western mountain ash, sequoia, interior live oak, scrub oaks and wild lilacs are Western natives.
Kentucky bluegrass, perennial rye, Bermuda grass, centipede grass and tall fescue are all non-native, invasive grasses identified by the U.S. Forest Service. They compete with native plants and invade natural areas when they are not managed as they are in lawns. Consider replacing them with native grasses and meadow plants to cut down on the investment of time and money to maintain your landscape. Minimize the lawn area by using native grasses and ground covers. The Audubon Society suggests starting small; use native bluestem, American seagrass, water sedge or woodland sedge as ornamental grasses. Use groundcovers around stone walks: sedum, thymes, creeping juniper, wild ginger and creeping phlox. Start a woodland garden in one corner of the yard and fill the understory with ferns, asters and other shade-loving woodland plants instead of grass.
Thousands of native plants provide blooms for landscapes. Arrange perennials so that something is always in bloom. Use columbine, Joe Pye weed, dog's tooth violet, purple coneflowers, black-eyed Susans; New York and New England asters; Rocky Mountain and Virginia iris. Grow cardinal flower, marsh marigolds and blue verbena in moist, shady areas. According to the Lady Bird Johnson Wildflower Center at the University of Texas, plants like fireweed, black cohosh, juneberry and Kinnikinnick attract butterflies, and deer avoid cardinal feather, Eastern red columbine and butterflyweed. Use the Center's extensive database to find appropriate plants for your area. Native plant societies and state university agricultural extensions also provide support for gardeners wishing to use native plants for xeriscaping or for wetland, woodland and rain gardens.