More of Your Wildlife Gardening Questions Answered

It’s Garden for Wildlife Month! For much of the country, the weather in May creates the optimal time for planting many species of trees and plants to ensure they get off to their best start, and it’s a great time for gardeners to get outside and welcome wildlife to their yards!

We recently answered some of your top questions about wildlife gardening. Here are answers to four more of your questions, this time with a focus on plants and the role they play in the wildlife habitat garden.

Why are native plants important?

Monarch on swamp milkweed. Photo by Jim White
Native plants support wildlife, such as this monarch butterfly on swamp milkweed. Photo by Jim White.

Native plants are the plant species naturally found in your region. Each region has its own unique plant communities that are adapted to the local soil types, climate, weather conditions, and moisture levels. That means that if you plant a native plant in its preferred conditions, once it’s established it won’t need any supplemental watering, fertilizer or pesticides to thrive.

Even more importantly, when it comes to supporting wildlife, native plants are always the best choice. Native wildlife and native plants evolved together over thousands of years, and their life cycles are in sync with each other. They rely on each other for survival.

For example, native trees and shrubs generally produce their fruits in late summer and fall. The fruits provide critical calories for migrating birds, and the birds spread the seeds of plants far and wide in return. These fruits also support non-migratory birds during the colder months when insects aren’t available. Butterfly caterpillars feed on the native plants with which they evolved. Each species can only feed on a limited number of plant species. Without these “host plants” butterflies cannot complete their life cycle and populations decline.

Lawns and other exotic ornamental plants that dominate the suburban landscape generally do not support wildlife or help keep your local ecosystem in balance.

Will tent caterpillars kill my tree?

Eastern tent caterpillars are a native species. Photo by Yankech Gary via Flickr Creative Commons.
Eastern tent caterpillars are a native species. Photo by Yankech Gary via Flickr Creative Commons.

Eastern tent caterpillars are a native species found over much of the eastern half of the United States. They turn into the tent caterpillar moth, a medium-sized, furry, pale brown moth. These caterpillars feed on the leaves of wild cherry, apple and crabapple, as well as hawthorn, peach, plum, pear and other members of the Rosaceae family.

The sight of your ornamental cherry or apple tree covered in silken tents made by hordes of tent caterpillars can be disturbing, but generally the damage that tent caterpillars do is cosmetic. A healthy tree, even if completely defoliated by tent caterpillars, will survive and put forth new leaves after the caterpillars have moved on.

As a native species, tent caterpillars are an important food source for native birds, including cuckoos and blue jays. So it’s best to tolerate the sight of the caterpillars and their tents for a few weeks. You’ll be feeding the birds and avoiding putting out toxic pesticides into the environment.

What’s the difference between “cover” and “places to raise young” in a wildlife habitat garden?

Frogs have different habitat needs in their juvenile tadpole phase than as adults. Photo by Mary Shattock via Flickr Creative Commons.
Frogs have different habitat needs in their juvenile tadpole phase than as adults. Photo by Mary Shattock via Flickr Creative Commons.

The four components of habitat that all wildlife need to survive are food, water, cover and places to raise young. Sometimes there’s confusion over the difference between cover and places to raise young. This is largely because many of the same landscape features that will provide wildlife with cover from predators or bad weather will also be used by wildlife as places to build their nests, lay their eggs, or give birth to their babies. A mature tree or a brush pile are great examples of features that provide both cover and places to raise young for wildlife (not to mention a source of food too–your plants can do triple duty).

Some species have completely different needs in their juvenile phase of life. Most frogs and other amphibians, for example, require a pond in order to lay their eggs and for their aquatic tadpoles to develop.  The same is true for dragonflies. Adult butterflies feed on flower nectar, but their caterpillars feed on the leaves of specific host plants. If you’re not providing habitat for wildlife in all phases of life, your habitat isn’t complete.

At the end of the day, “places to raise young” is its own habitat component because creating a wildlife habitat garden isn’t just about feeding individual animals or providing them with water or cover. It’s about giving the local wildlife the resources they need to survive and reproduce so their populations remain strong.

Can Native Plants be Invasive?

Photo Credit: Anita Gould/Flickr Creative Commons
Common milkweed is a native plant that can be aggressive in a garden setting, but by scientific definition is not invasive in its native habitat. Photo by Anita Gould via Flickr Creative Commons.

No, native plants cannot be invasive in their native habitat. Ecologically, the term invasive has a specific scientific definition. It refers to any organism introduced by human actions (deliberately or otherwise) into new ecosystems where they didn’t naturally evolve. It only applies to exotic species. A plant can’t invade an ecosystem to which it’s already native.

Sometimes there’s confusion on this point because in gardening vernacular, the term invasive is often used casually to mean any aggressive plant that might overtake your garden beds. While some native plants can be aggressive in the garden setting, and can even migrate out of your yard into natural areas, the effect is radically different than when an exotic species becomes invasive.

Invasive exotic species don’t support the natural diversity of wildlife, and overtake the native plant communities that many wildlife species rely on for habitat. When an aggressive native leaves your yard, it’s simply going home and will offer habitat to wildlife in the wood and fields just like it did in your yard.

Learn MoreSubscribe to the Garden for Wildlife newsletter for more gardening tips!