From the forests of western Maryland to the brackish marshes of the Chesapeake Bay to the sandy beaches of the mid-Atlantic coast, Maryland's diversity of ecosystems supports an equally diverse array of native plants. The following species are just a small representation of the flowers, trees and other plants you can find in our home state—how many can you find and record this upcoming weekend during the City Nature Challenge?
A perennial spring wildflower, the foam flower can be found in woodland ecosystems throughout eastern North America, oftentimes along the shaded banks of streams. It gets its common name from the cloud-like appearance of the clusters of small, white-pink flowers that bloom from long, thin stems. This native plant has heart-shaped leaves and can grow to be 1 to 3 feet tall. Its genus name—Tiarella—translates to little tiara and refers to the crown-like shape of its seeds.
The river birch—unsurprisingly—grows naturally along the banks of rivers and streams, where its root system helps to prevent erosion. These native trees can grow to 40 to 70 feet tall, with trunks that are about 2 feet in diameter. Like most birches, the leaves are diamond-shaped and have serrated edges, and the bark on a mature tree peels and curls in paper-like sheets. In the spring, the river birch produces catkins—slender, cylindrical clusters of flowers—that hang from the end of twigs and release copious amounts of pollen.
The leaves—known as fronds—of a Christmas fern are about 1 to 3 feet long, and there are two types: those that produce spores, and those that do not. The sterile fronds that do not produce spores are evergreen, remaining glossy and green throughout the winter and the holiday season, which gives this native plant its common name. Christmas ferns grow naturally on slopes in wooded habitats, where their low-laying fronds provide protection on the forest floor for a variety of species. If you see this plant in its natural habitat in the spring months, you'll notice tightly coiled developing fronds—called fiddleheads—that are covered in silvery scales.
The name of the genus for this native tree—Diospyros—translates to "fruit of the gods," and refers to the popular yellow-orange fruit that this native tree produces in the fall. Many animals are known to eat this fruit, including raccoons, coyotes, bears, deer and many species of birds. You'd be wise to avoid eating an unripe persimmon—because of the high levels of tannins present in the fruit, they're very astringent and unpleasant to eat before they're fully ripe. Besides its fruit, one of the more distinctive characteristics of this tree is its grey-brown bark that has a scaly appearance. These trees sport thick, green, oval-shaped leaves that grow to 4 to 6 inches long, and mature trees can be 20 to 60 feet tall. In the spring, persimmon trees bloom with yellow-white flowers, which are pollinated by several species of bees. Over 45 species of butterflies and moths lay their eggs on these native trees.
Common milkweed can grow to be about 5 feet tall, and its small, sweet-smelling, pink-purple flowers can be found in clusters at the top of the plant. This native flowering plant serves as a food source for more than 400 species of insects—perhaps most notably in our region, the monarch butterfly. Milkweed is critical to the survival of the monarch; it's the only plant that monarch caterpillars will eat, and the only plant that reproducing monarchs will lay their eggs on. Most animals cannot eat the leaves and stems of the milkweed plant because they contain toxins called glycosides. Monarch caterpillars are immune to this toxin, and consuming milkweed leaves makes them toxic for predators to eat. As a caterpillar and butterfly, monarchs are brightly colored to warn predators not to eat them. Birds that don't heed this warning and attempt to eat them will become sick and avoid eating monarchs after this experience.
The Issue with Invasives
The foam flower, river birch, Christmas fern, common persimmon and common milkweed are all examples of Maryland's native plants, which are species that have evolved over thousands of years in a particular region and have adapted to that region's climate, geology and soil conditions. Native plants are critical in supporting local wildlife—including pollinators—as well as migratory species, and they help improve local water quality because they do not rely on fertilizers and pesticides to grow.
On the flip side, non-native plants are species that were introduced to an area where they did not evolve, and they can wreak havoc on the natural balance in these ecosystems and become invasive. When there are no natural controls to limit the spread of invasive plants, they outcompete native plants for sunlight, water and nutrients. As a result, native plants—and the support system for native wildlife that they provide—begin to disappear.
Supporting Native Plants
At the National Aquarium, we've been working closely with state legislators to support legislation that promotes native plants in Maryland and reduces the harmful impact of invasive plants. Starting in 2021, the National Aquarium helped author and pass legislation that prohibits the use of state funds to purchase invasive plants, sponsored by Delegate Eric Luedtke. Building on the success of this legislation, this year we also helped to author and pass legislation that requires the state to expand its current list of invasive plant species from 19 to more than 80. These 80-plus species, documented by the National Park Service and the U.S. Fish and Wildlife Service in the "Plant Invaders of Mid-Atlantic Natural Areas" handbook, are by no means all of the plants that are invasive—or are at risk of becoming invasive—in the mid-Atlantic, but they are the most problematic species. The legislation, which was sponsored by Senator Sarah Elfreth and Delegate Eric Luedtke, will help improve understanding of what not to plant, and also requires entities that receive state funding to prioritize the use of native plants for every planting project.
The work to support native plants doesn't stop there. Over the past 20 years, the National Aquarium has planted 2 million native plants throughout the Chesapeake Bay watershed through habitat restoration efforts. We have also supported homeowners in native plant gardening by partnering with the National Wildlife Federation in the Garden for Wildlife program, which provides education on the importance of native plants, guidelines for creating a native garden and certification for backyard wildlife habitats. Through the certification of hundreds of residences, schools and places of worship, Baltimore became a certified Community Wildlife Habitat in 2015.
Are you ready to do your part in supporting native plants and wildlife? Create your very own backyard wildlife habitat and have it certified through NWF—your local ecosystem will thank you!