by Ann Farnham, LLA

Why do we emphasize using native plants? What are native plants? Are they better than introduced, exotic, non-natives? Why does the Ewing Township Code, Landscaping, require at least 45% native plants in all non-private property planting plans?

A native plant is one which, over countless years, developed with our environment’s soil types, precipitation, temperatures, elevations and exposures. A good definition of a native plant is one that existed, in any specific region, before the European settlement in this country. Our region is the Mid Atlantic Region.

Since that European settlement, hundreds of plant species have been introduced from many parts of the world. They are often very beautiful, sometimes seem to fit a specific need, might grow easily, and show off an owner’s sophistication and botanical interests. Many, however, have turned out to be invasive and some are toxic to people and wildlife.

Native plants, then, are adapted to their particular regions, in our case, the Mid-Atlantic. They are compatible with the physical geography and factors mentioned above. As a result, they require, after establishment, much less maintenance, less water, and do not require chemical applications of fertilizers, pesticides, and soil amendments. Birds, butterflies, beneficial insects, reptiles and mammals rely on their fruit, nuts, nectar, and seeds. Many birds depend upon native plant insects, such as caterpillars. Many alien plants are toxic to these native insects.

Imported exotics interrupt the food web by frequently out-competing the natives for space, exposure and nutrients. They usually do not support the insects upon which our bird population depends. For example, one brood of Chickadees requires 6000 caterpillars as food by the time it attains maturity (birds require the protein and fats from insects in order to mature or to lay eggs; in non-breeding times seeds and fruit do the job). A native oak, for example, can support more than 500 species of caterpillar, whereas a non-native Gingko only supports 5 species. Bird populations are in steep decline, certainly not only the result of habitat loss.

Our penchant for beautiful, green lawns has destroyed functional ecosystems by the use ofchemicals. In the process our waterways, air and health become polluted as well. The lawn mower itself compacts the soil and emits pollution where there used to be meadows, fields and woodlands, now lost to urbanization. We need to develop yards and gardens with friendlier habitats by using native trees, shrubs and flowers, and reducing lawn areas.

Many of our native plants have died or been seriously compromised with introduced pests such as the Emerald Ash Borer (ash trees), the Wooly Adelgid (hemlocks), the Japanese Beetle (almost everything), and fungal diseases brought in by the nursery trade. The attached Native Tree List has several trees, such as the Ash, Eastern Hemlock, American Sycamore and Flowering Dogwood, which now should not be used at all. Some selected, resistant varieties of Flowering Dogwood, however, are available such as the Rutgers-developed Cherokee series.

We want to recommend three books for your further understanding in alleviating the problems above.

1. Bringing Nature Home by Doug Tallamy;
2. Native Plants of the Northeast by Donald Leopold;
3. The Brooklyn Botanical Garden’s Native Alternatives to Invasive Plants.

In addition, be sure to visit the web sites www.npsnj.org/plant-lists-native/trees_ for_ landscaping and plants.usda.gov.

See also, the Native Plant Society of NJ’s excellent list in Native Trees for Residential Gardeners.

The  Ewing Environmental Commission welcomes suggestions for the Plant of the Month from all Ewing residents.

To calculate the value that trees add to your property, go to tree benefits.com/calculator/