The importance of planting native

Over the last decade or so, there’s been a heavy emphasis (with strong scientific evidence to support it) about the importance of planting native trees and shrubbery on residential properties and communities. The emphasis on planting native cannot be overstated, especially here on the Eastern Shore.

Across the spectrum of organisms, numerous species of insects, birds, mammals and amphibians are in some way threatened or in decline. There are variety of reasons for these declines, including habitat loss, pesticides, climate change, and loss of native plants.

Planting native trees and shrubs instead of ornamental non-native species can help turn the tide in support of a stronger, healthier, local ecosystem. Here’s an example of why planting native is so important. According to best-selling author and naturalist, Doug Tallamy (“The Nature of Oaks” 2021), “…a single oak tree is the host to some 534 species of moths and butterflies.” When you add in the number of other insects, birds and mammals that are reliant on those insects for food, the number of organisms dependent on the linkages to the Oak tree goes even higher!

Over thousands of years, flora and fauna that are native to a particular region, have developed and adapted together, often creating specialized, symbiotic partnerships where both organisms benefit from the other. At the same time, insects, birds, and mammals that are indigenous to a region are likewise dependent on native trees and shrubs throughout the year, for food and nesting sites, all of which contributes to a healthier environment.

By contrast, an introduced, non-native, ornamental Bradford Pear hosts only a minuscule fraction of insects compared to the Oak.

Unfortunately, the story doesn’t stop there. As invasive trees like Bradford Pears invade the landscape, they can disrupt and eventually decimate a surrounding ecosystem. Each time a native tree is displaced by a non-native tree, the result is fewer insects, fewer birds, fewer animals, and an ecosystem that can begin to collapse on itself.

Here on the Eastern Shore — in the heart of the Atlantic Flyway — migrating birds need the insect nutrition that native trees and shrubs help support. This is especially important during the Spring and Fall migration period. In fact, one brood of Chickadees requires some 3,000 inchworms (small caterpillars from moths and butterflies) in just one season! Take away that important food source, and you’re negatively impacting a valuable member of bird species that is native to the Eastern Shore.

Unfortunately, many of the ornamental, non-native plants sold at garden centers, host no native insects at all, ultimately leading to a decrease in biodiversity. In fact, some of those non-native plants can be downright dangerous! One example is the Asian Nandina plant which is sold at “Big Box Garden Centers”. This cheap, popular landscaping shrub, with its bright orange berries, might be aesthetically appealing to the human eye, but the Nandina does little to support native insect species. Worse, their berries contain a toxic hydrogen cyanide compound that is fatal to a wide variety of animals and birds, especially the Cedar Waxwing and American Robin.

Insect decline is real and it can have a devastating effect on a region’s biodiversity. According to numerous studies across the globe, insect populations are suffering. Oliver Milman, author of “The Insect Crisis” indicates that “…flying insects have declined by 75% in the last 25 years”.

Here’s the good news. Everyone can help support their local ecosystem by planting trees and shrubs that are native to the region, resulting in more birds and mammals that are crucial in supporting a healthy environment.

The top ten best trees for the Eastern Shore that help support healthy biodiversity are:

1. Oak

2. Cherry

3. Willow

4. Birch

5. Tulip Poplar

6. Crabapple

7. Blueberry

8. Maple/Box Elder

9. Elm

10. Loblolly or White Pine

The Maryland Department of Natural Resources (www.dnr.maryland.gov), The Maryland Native Plant Society (www.mdflora.org) and the University of Maryland Extension office (www.extension.umd.edu) all provide excellent information and resources on how best way to support nature by planting native trees and shrubs.

Jay Falstad is a Maryland Master Naturalist and Executive Director of the Queen Anne’s Conservation Association. For comments, questions, or suggested topics about Eastern Shore nature, email him at jayfalstad@gmail.com