The Importance of Native Plant Species in Our Landscapes

When non-native or exotic invasive plants are introduced to an area and have no natural predators, they can displace native species. Many of these were intentionally brought to North America as ornamentals from other continents. They often have attractive flowers, foliage, or fruit, but “invasives” disrupt natural ecosystems, wildlife food sources and habitats, water flow, and soil health. Invasive exotic plants may also produce lots of seeds that can spread into woodlands. Some examples are Callery/Bradford pear, Chinese privet, Chinese and Japanese wisteria, and Chinese elm. Others produce a thick canopy and shade out native species or substances that prevent seed germination, like Asian Honeysuckles and Oriental Bittersweet.

In the past we gardened for food consumption, then aesthetics. Now, with changing climate and loss of habitat beauty alone should not be the only justification for selecting a plant for the landscape. Native shrubs, vines, and trees support insects, such as adults and larvae of beetles, butterflies, moths, ants, and flies. Certain insects depend on native flora as hosts for the larval stage and the berries and seeds for adults. Studies have shown that birds need a lot of insects to feed and fledge their chicks, with at least 70% native vegetation. Food webs depend on plants for energy, oxygen, and carbohydrates. Decomposing leaves build soil; the leaf litter and humus are essential to the microbes that recycle those nutrients.

Right Plant Right Place

When selecting plants for our landscapes, we consider form, mature height and width, and site conditions like light, moisture, and hardiness. Just as important are the ecological services that a species offers. Our native grasses, perennials, trees, shrubs, vines, and groundcovers are often the best choices for preserving ecosystems, using fewer pesticides and irrigation because they are adapted to the climate, heat, and humidity of our region. Please do a little googling or check your local extension service to understand the needs of a specific plant.

Knowing what to ask for when shopping at a garden center is key. Common names can vary regionally, so knowing the scientific name (genus and species) will avoid any confusion. There are many species of oaks, hollies, and laurels, and sometimes the common name or scientific name may indicate the origin of the plant, for example, Chinese silvergrass (Miscanthus sinensis), Japanese wisteria (Wisteria japonica) or American elm (Ulmus americana).

Attractive not only to birds, butterflies, and other wildlife, native herbaceous and woody species can give seasonal interest and beauty. Flowering perennials, such as coneflower, passion vine, and lobelias, appeal to gardeners and offer another way to attract creatures other than just having feeders. Plant them (native plants), and they (birds, bees, and butterflies) will come.