Fall Color Isn’t Just for Trees

Smooth Cordgrass (Spartina alterniflora)

Fall on Delmarva brings an explosion of reds and golds in the woods as chilly mornings and shorter days arrive. Autumn is one of the most beautiful times of year in our watershed. Fall foliage displays near their peak in early November, so it’s a great time to get outdoors.

In the Inland Bays, vibrant fall color is not limited to the woods. Our thousands of acres of salt marsh also change with the seasons. In autumn, the lush greens of cordgrass meadows gradually turn to golds, purples, and reds.  Colors seemingly change by the minute and are particularly dramatic when lit by the setting sun.

Animals of the marsh also are in transition. Migrating songbirds and shorebirds have been moving through, often stopping to forage for food that fuels their journey south. Ospreys also have moved on to warmer climes. The abundant waterfowl that winter in the Bays have begun to arrive, and many will feed or shelter in the salt marshes. In fall and winter, Northern Harriers and Short-eared Owls can be seen gliding low over the marshes as they hunt. Diamondback terrapins soon will hibernate, burying themselves in the mud at the bottom of tidal creeks.

Autumn is an amazing time to visit the salt marsh! Here are a few special native plants to look for when you’re there.

Smooth Cordgrass (Spartina alterniflora)

The most prominent feature of Inland Bays low marsh areas, smooth cordgrass is a fascinating plant. Shoots of this warm-season perennial sprout from rhizomes anchored in the mud, and in summer the plants are brilliant green.  As fall approaches, golden seed heads appear, and by winter the plants turn brown and die off. The dead, decaying grasses are a critical source of organic material that nourishes the entire marsh ecosystem.

Take a close look at the cordgrass growing at the edges of tidal creeks, and notice the numerous ribbed mussels growing among its stems and roots.  The roots and attached mussels protect marsh edges from eroding waves. The mussels also filter nutrients from the water and deposit them as pseudofeces among the roots, nourishing the plants.

Spartina alterniflora is well-adapted to its harsh salt marsh environment. Glands on its leaves excrete salt, allowing the plant to survive inundation by saltwater for up to 20 hours a day. Special tissues in the plant also transport oxygen to stems and roots that are submerged in anoxic water and mud.  The white or pale purple flowers of the native salt marsh aster (Symphyotrichum tenuifolium) often can be spotted among the cordgrass in late summer and fall.

Glasswort (Salicornia spp.)

Glasswort (Salicornia spp.)

The fleshy, jointed stems of this unusual, salt-tolerant succulent turn bright red in autumn and provide a lovely flush of color in low areas of the salt marsh. Several species occur in our area. The common name glasswort comes from its historic use as a source of soda ash for glassmaking.

Other common names for this plant – pickleweed, sea bean, sea asparagus – give hint not only to its appearance, but also to its edibility.  In fact, the green stems have a natural salty flavor and are considered a delicacy by many. One can easily find recipes online. Its high vitamin content and medicinal qualities made glasswort popular with sailors, who used it to fight disease during long voyages.  In the salt marsh, glasswort serves as food for waterfowl.

Sea Lavender (Limonium nashi)

Sea Lavender (Limonium nashi)

Sea lavender is an annual flowering plant common in Irregularly flooded areas of the high marsh. In late summer and early fall its green basal leaves are topped with numerous small purple flowers blooming on a single stalk.

By mid- to late-fall, the plants dry and turn brown. Sea lavender’s beauty has long been recognized by horticulturists, and it’s a great choice for a native plant garden.

Groundsel Bush (Baccharis halimifolia)

Groundsel bush, also known as high-tide bush or sea myrtle, is a showy plant of high marsh areas that are only occasionally subjected to tidal flooding. It is the only native eastern species of the aster family that grows to tree size. Male and female flowers occur on separate plants. In September and October, female groundsel bushes sport dense clusters of feathery silver-white seeds that persist into early winter.  The genus name Baccharis is derived from the cottony seeds that are reminiscent of the flowing white beard and hair worn by Bacchus, the Greek god of wine. Although the plant is browsed by white-tailed deer, it’s thought to be toxic to many wildlife species. The bark and roots were made into a tea by Creoles to treat tuberculosis.

The salt marshes of the Inland Bays are a highly productive, but fragile ecosystem. These tidal wetlands reduce flooding and erosion from storms, filter pollutants, trap and store carbon, and provide critical habitat for fish and wildlife. But nearshore development and sea level rise now threaten these ecosystems. Protecting and restoring them is a priority for our Bays.

Groundsel Bush (Baccharis halimifolia). Left and Right photos by Dcrjsr via Wikimedia


Posted Under: Staff Blog