No offense to admirers of the red leaves and berries of nandina shrubs and the way butterfly bushes attract pollinators, but these foreign invaders are prime examples of why planting native species is a much better option for the ecosystem.
Planting native species helps an ecosystem function as it should.
Birds eat nandina berries and disperse them in the wild with their droppings to the point where nandina bushes can crowd out native plants. According to the Audubon Society, nandina berries contain cyanide and can make birds sick or even cause their death.
Butterfly bush flowers produce large amounts of nectar but research indicates that it lacks nutrition for our native pollinators, so it’s like junk food.
The dust-like seeds of butterfly bushes are easily carried from yards by the wind and are deposited along road, inn fields and elsewhere. Without natural predators, non-native plants and insects alike rapidly spread and out-compete the natives. Our changing climate tends to help non-native plants and insects spread.
A good host plant will support the entire life-cycle of a species and the butterfly bush only supports the adult stage for butterflies. Unlike native host plants such as milkweed, caterpillars that become butterflies and other native insects don’t feed on leaves of butterfly bushes.
Native plants, insects and animals formed symbiotic relationships over the thousands of years they co-existed and therefore together offer the most sustainable habitat. They’re generally able to flourish where they originally existed without human assistance.
Spicebush is a good native alternative to nandina bushes and mountain laurels can be planted instead of butterfly bushes.
A plant is considered native if it is present naturally and not because of humans.
Non-natives are considered invasive if they out-compete natives and destroy natural habitat. Prolific growth by a single plant species can be harmful because forests with a limited number of plant species provide very poor habitat for wildlife.
Native plants are important to birds and other wildlife because of the insects they attract. Almost all land birds require insects to feed their young. Even seed-eating birds often must feed their babies insects to ensure their survival. Insects can’t adapt to eating non-native plants.
According to the Audubon Society, a native oak tree can support the caterpillars of over 500 species of butterflies and moths. Those caterpillars are a critical food source for over 96% of songbirds. For example, a pair of Carolina chickadees requires between 6,000 and 9,000 caterpillars to successfully raise just one brood of young.
We can help stop the non-native plant invasion by using and nurturing native plants around our homes, businesses and on public property. Native plants generally do well and require less care than non-native species when grown where they naturally belong.
All non-native plants don’t become invasive, and most can safely be planted as ornamentals. However, it takes scientists years or even decades to fully understand an introduced plant’s potential invasiveness. The Wilkes Cooperative Extension Service is a good place to start to learn if something is considered invasive.
Many native plants produce brilliant fall foliage and flowers that are just as showy as non-natives.
There are several websites with good information about native plants as alternatives to non-natives, determining which should be planted in different parts of North Carolina, where they can be purchased and related information.
• North Carolina State University’s “Landscaping for Wildlife with Native Plants,” at https://content.ces.ncsu.edu/landscaping-for- wildlife-with-native-plants;
• National Wildlife Federation’s Native Plant Finder at https://www.nwf.org/native
• N.C. Botanical Garden in Chapel Hill at https://ncbg.unc.edu/plants/resources- for-gardeners. Native wildflowers, shrubs, trees, grasses, vines and ferns are grown in its nursery and greenhouse and are available for the public to buy. It also has information about invasive plants.