Native Plants Make a Difference (no fooling!)

Tiny Anemone quinquefolia

Plants are plants are plants, right? They all make oxygen – check! Many of them have pretty flowers for bees and butterflies – check! Some of them make fruit for birds – check!

So what is the big deal about native plants? Why should we have to look harder to find these darn native plants when the nurseries and the big box stores have oxygen-making, flowering, and fruiting plants for our yards?

The reason that native plants make a difference is that, in study after study, research demonstrates that non-native plants don’t support pollinators and birds on an equal scale with native plants.

Let’s start with birds. The worst news is that the fruit of non-native nandina (Nandina domestica) can kill cedar waxwings that gorge on it (and gorging is one of their natural feeding behaviors). At least two reported incidents have been documented (including this one in 2017 near Atlanta) but certainly there would be some unreported deaths as well. Even for non-poisonous berries, the nutritional value of the non-native fruit can be lower than the value of the native plants it replaced.

American plum (Prunus americana)

Fruits of the non-native buckthorn – which creates dense competitive thickets, displacing native fruit plants – are lower in fat, requiring migrating birds to eat more of them. The same is true in Georgia for privet (Ligustrum sp.). Some studies have shown that, in areas where both native and non-native fruits are present, birds eat the native fruits first. Other studies report increased amounts of birds of concern in suburban yards that have more native plants.

The bad news continues for birds, however, and here is where insects are affected as well. Insects in your area didn't evolve with non-native plants so butterflies and moths can rarely use them as host plants. As a result, populations of those insects decline (you've heard about the monarch butterfly's decline in population, right?). In addition, all the birds that feed caterpillars to their babies have to work harder in an area with non-native plants to find food for them (and usually they create fewer nests). From this article about buckthorn (again, a similar invasive to Georgia's privet infestations):

Buckthorn and other exotic plant species can take over a plot of land, squeezing out native plants. Insects with plant-specific diets might find their necessary plants disappearing or gone.

If parent birds hunt buckthorn or certain other invasive shrubs for nestling food, they could be wasting time and energy. If near-nest vegetation is buckthorn-heavy, for instance, the parents must fly farther and work harder at procuring food.

Studies have shown that thickets colonized by exotic plants have fewer songbirds, and those birds had lower reproductive success. Birds that do choose to nest in such areas needed larger territories to support successful nesting. That can increase territorial competition and/or mean fewer nesting birds in a given area.

Southeastern blueberry bee on blueberry

In addition to the insects that depend on foliage to eat, other insects are affected by the flowers available. Some insects, bees particularly, can be floral specialists. The spring beauty bee and the Southeastern blueberry bee both depend on specific native flowers.

So, stop fooling the birds and native insects and get what they really want. Native plants make a significant difference when it comes to supporting our pollinators and birds.

We are in the middle of the season of spring native plant sales. Get out there and get some native plants!