Taking a Local Approach to Growing Vines
Eye-catching native plants attract wildlife to your garden
LIKE A CREATURE in a horror movie, an Asian vine called Old World climbing fern has swallowed up more than 100,000 acres in South Florida. Originally imported to this country in the mid-1900s for use as a foliage plant for hanging baskets, this exotic raced out of control when wind and wildlife began spreading its reproductive spores. It is now smothering songbird habitat in Loxahatchee National Wildlife Refuge and taking dead aim on Everglades National Park.
Throughout the United States and Canada, many other invasive species of vines are choking out native vegetation and harming wildlife. Some nurseries still sell several of these villains--such as oriental bittersweet, porcelain berry, English ivy and Chinese wisteria--to unsuspecting gardeners. Most botanists believe that you can help keep this ecological nightmare from getting any worse by planting only native vines. In the process, you will add eye-catching, flowering plants to your yard that will help you attract birds, butterflies, bees, moths and even some small mammals.
Instead of planting Japanese honeysuckle, which climbs over vegetation and kills shrubs and small trees by cutting out their light, try one of the North American honeysuckles. Bruce Newhouse, a botanist and president of the Native Plant Society of Oregon, suggests orange honeysuckle (Lonicera ciliosa). Found throughout the Pacific Northwest, this vine has clusters of orange-red flowers. Another possibility is purple honeysuckle (Lonicera hispidula), which has purplish pink flowers and is native from British Columbia to California. "Hummingbirds are attracted to both of these vines," says Newhouse.
Gardeners in the East can plant trumpet honeysuckle (Lonicera sempervirens), which seldom grows more than 15 feet high and is a good choice for small yards. Hummingbirds and even orioles drink the nectar from its crimson flowers. Catbirds, mockingbirds and thrashers eat its fall fruits.
Another vine that attracts wildlife is Virginia creeper (Parthenocissus quinquefolia), a native of the eastern half of the United States. Many types of birds, including several species of woodpeckers, devour its small, blue-black berries. A high climber, Virginia creeper can cover walls or fences, works well growing over a brush pile and makes an excellent ground cover. Judith Phillips, a New Mexico garden designer, says westerners can use a similar plant called woodbine (Parthenocissus inserta).
In making decisions about which species to plant in a yard, Phillips recommends that gardeners "think locally." For one thing, a plant native to your region will be adapted to your climate. Secondly, many vines taken out of their natural environment can become invasive, even if they are just moved to another part of the country.
American bittersweet (Celastrus scandens) is another example of a native that is an ideal choice for certain areas of eastern North America. This native bittersweet grows to 20 feet or more and has decorative orange-yellow pods, which open in autumn to reveal scarlet seeds--an important food source for songbirds, grouse, quail, chipmunks and fox squirrels.
A perennial called pipevine also provides essential nutrition for wildlife; it is the only food plant for the caterpillars of pipevine swallowtails, elegant blue-and-black butterflies found across much of the United States. "Without such larval food plants, we won't have butterflies," says Doug Tallamy, a professor of entomology and applied ecology at the University of Delaware. He points out that butterflies may be attracted to the nectar of certain exotics. "But they won't lay their eggs on them," he says, "because the caterpillars would starve."
Both the eastern species of pipevine (Aristolochi durior) and the West Coast variety (Aristolochi californica) lure the swallowtails. A deciduous vine with heart-shaped leaves and unusual flowers that look like the bowls of a Dutchman's pipe, the plant was widely grown during the Victorian era. Today, it is becoming popular again and biologists believe the number of pipevine swallowtails is increasing as more people use this fast-growing native to shade or screen their decks and terraces.
Passionflower vine is another butterfly larval plant recommended by Tallamy. Several types of butterflies, including gulf fritillaries and zebra longwings, prefer to lay their eggs on a southeastern passionflower called maypops (Passiflora incarnata). Its intricate lavender and white blooms also bring in many other butterflies as well as hummingbirds. In the fall, yellow fruit attracts small mammals such as opossums. This vine is usually "well behaved," growing from about 6 to 12 feet long.
Phillips suggests another low-growing vine called twining snapdragon (Maurandya antirrhiniflora). Also known as the hummingbird vine, this southwestern plant produces wine-colored flowers. It is easily trained to grow straight up strings suspended from the top of a balcony, making it an excellent choice for apartment and condo dwellers. Other natives to try growing in your garden area include crossvine (Bignonia capreolata), fox grape (Vitis labrusca), Jackson vine (Smilax smallii), western white clematis (Clematis ligusticifolia), curly clematis (Clematis crispa) and American wisteria (Wisteria frutescans).
To determine the best natives for your area, check with nearby nurseries that specialize in local, native plants. You can often locate these nurseries by contacting a regional native plant society. When searching for a particular vine, don't rely on the common name. It often varies from region to region. Always check the Latin or scientific name, or you might inadvertently end up planting an invasive variety.
"In our studies, we discovered native insects rarely eat nonnative plants," Tallamy says. "They don't have the enzymes required to digest the leaves of exotics." When out-of-control alien vines obliterate native plants, insects lose their food sources and their numbers drop. "Since many birds feed insects or insect larvae to their young," he explains, "when insects decline, so do the birds."
It's no secret, the ecologist points out, that suburban areas are fast becoming dominant "ecosystems" in this country. "If homeowners would use only plants that are native to their area," he urges, "just imagine the future impact on wildlife populations and our natural heritage."
Doreen Cubie wrote about
in the June/July issue.
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