Why Plant Natives?

Alison Milligan, local native plant expert and volunteer extraordinaire, spends most days discussing the benefit and urgency of using more native plants - trees, shrubs, perennials - in communities and home landscapes.

“Plants that are native to Maryland provide function and habitat that exotic or invasive species don’t provide,” Milligan said. “They create ecosystems that increase biodiversity, which makes the environment healthier for everyone and everything. Our plant choices matter, now more than ever.”

Milligan added, “We need to rethink our relationship to nature. There are many plants that are specific to the needs of insects, birds and animals in our environment. If natives are no longer present as a resource, then the complexities within the natural environment can be irreversibly broken. The monarch caterpillar’s dependency on milkweed is a classic example; without milkweed, there will be no monarchs.”

Milligan started gardening at 20 years old while she was serving in the U.S. Air Force. She began by growing tomatoes and pumpkins and she had her first compost. Each year, she has continued to experiment by growing more varieties of vegetables and flowers.

“It wasn’t until I became a Master Gardener and then a Master Naturalist that I fully comprehended the value of native plants and the vital role they play in supporting life; from butterflies to bass (rockfish) to barred owl, they are the foundation of the food chain for these lifeforms,” Milligan said. “Once I made the connection, there was no turning back.”

Now, 40 years later, aside from Milligan’s impressive bachelor’s and master’s degrees in electrical engineering, she has accrued substantial credentials because of her extensive studies and volunteer work for several Maryland programs. In addition to being a Maryland Master Gardener and Naturalist, she’s a Watershed Steward and a graduate of both the Chesapeake Bay Landscape (CBLP) and HoLLIE (Howard County Legacy Leadership Institute for the Environment) programs.

This year, Milligan received certification as a tree trooper for the Replant Anne Arundel program and is helping to plant more resilient tree species in the county.

“These programs work in specific ways to educate and serve residents by planting the right native plants to solve common landscaping problems, create habitat, and improve the health of our air and water,” she said.

Milligan’s home landscape is almost entirely natives and requires little to no care throughout the seasons since nature’s beauty unfolds at its own pace without the need for a lot of time and energy on her behalf.

“I don’t have time to fuss over plants; that’s the advantage of natives - it’s all about ‘right plant, right place,’” Milligan added. “The design logic I learned in engineering complements my interest in nature. I am logical about testing and assessing a plant’s individual requirements and utility; I document and photograph them throughout the seasons to understand how they compete, what life they support, and how effectively they solve problems. Most of the gardening I do now is pulling invasive weeds and planting natives in their place.”

Milligan is also a hero to people in the local community who are interested in learning and volunteering in their own neighborhoods; she gives free “house calls” and provides valuable advice on what and where to plant natives. Her early inspiration came from Dr. Doug Tallamy, an entomologist and professor at the University of Delaware and author of the book “Bringing Nature Home: How You Can Sustain Wildlife with Native Plants.”

Tallamy explains in his numerous books the vital connections between plants and insects, and how these interactions are important to all species, including humans.

“The loss of insects means the loss of all, or most of, a food source for toads, skink, birds and mammals,” Milligan said. “They are all a part of the food web that is sustained by native plants.

“Planting a diversity of natives is important because that’s the key to creating a thriving healthy ecosystem,” she added. “Natives support beneficial insects like ladybugs, ground beetles, and spiders that eat garden pests like aphids, slugs and mosquitos. The common practice of using insecticides upsets the balance of nature because not only does it kill nuisance bugs but also the beneficial insects, including bees. Eliminating bees from our environment is not an option - they pollinate over 80 percent of all flowering plants, including food crops, like my blueberries.”

Not only do exotic or invasive plants outcompete native plants, but they also don’t provide the resources that sustain local fauna, in some cases, they harm them.

“Heavenly bamboo (Nandina spp.), a commonly sold Tier Two invasive shrub, has berries that contain cyanide,” Milligan said. “Cedar waxwings are the type of birds that gorge when they feed; if they feed on the berries of this shrub, they get sick and often die.”

Milligan said many native plants solve problems and fit the average homeowner aesthetic. Oak (Quercus ssp.) and river birch (Betula spp.) trees provide exceptional benefit to the Chesapeake watershed and local fauna. Inkberry (Ilex glabra), winterberry (Ilex verticillata) and sweetspire (Itea virginica) are commonly sold shrubs that compliment most landscapes - they are excellent alternatives to Tier Two invasive plants like burning bush (Euonymus spp.) and barberry (Berberis spp.) which threaten habitats, and in the case of barberry, increase tick populations.

“There is a lot the average homeowner can do to create a healthier environment at home,” Milligan said. “Reducing your lawn, avoiding pesticides, removing exotic and invasive plants, and controlling your stormwater runoff can all be accomplished using native plants. I use them all in this way and I take great satisfaction knowing I’m improving the quality of the air, water and habitat for native species, including humans.”

To learn more, download the U.S. Fish and Wildlife Service’s native plant guide: www.fws.gov/chesapeakebay/resources/native-plants.html The University of Maryland Cooperative Extension’s website, extension.umd.edu, is also a resource for home gardeners and potential volunteers.