Spartina angelica • Class A

Spartina anglica is a stout, rhizomatous salt marsh grass. The stiff plant grows from 1 foot tall in the spring, up to heights of 6 feet in fall. Young healthy green shoots and leaf sheaths are often streaked with red or purple just below the sediment surface. Its green leaves are flat and smooth on both upper and lower surfaces tapering to a small sharp tip and having concave sides just before the tip. Common cordgrass also has rows of hairs where the leaf meets the stem (ligules) that are up to a third of an inch long, compared to the smaller 1/5th “ length of the smooth cordgrass ligules. It has many inflorescences (clusters of flowers) which are 4 to 18 inches long with 3 to 30 branches (spikes) per inflorescence. 

This cordgrass, like other non-native species of Spartina, traps sediment, builds marshes from the edge out, and overgrows native vegetation. It alters the native ecosystem and produces monocultures that have much less value as habitat for feeding and roosting of shorebirds and other wildlife, than native marsh flora. Loss of beach habitat and navigation routes and reduced water access are a result of the spread of Spartina. Therefore, activities, such as fishing, hunting, boating, bird watching, botanizing, and shellfish harvesting are also negatively impacted. 

Common cordgrass usually flowers after 1 or 2 years, in late July to September. Ripe seeds fall from October to January. Vegetative fragments may spread year round 

Seeds are spread by wind and water currents, but can also spread vegitatively by rhizomes and fragments that break off and move downstream. 

Pulling out seedlings is an effective method of control. Care must be taken to remove both shoots and roots. Once the plant begins to put forth new shoots, hand-pulling may break off portions of root, allowing the plant to re-sprout. Seedlings generally begin this process late in their first growing season. Repeated pulling will eventually kill small plants.

Mowing infestations can contain growth, limit seed set, and eventually kill the plants. To be effective, clones must be mowed repeatedly, beginning with initial spring green-up and continued until fall die-back. For clones under 10 feet in diameter, one to three mowings during the growing season may be effective. 

Since Smooth Cordgrass is found in aquatic areas, the use of an herbicide formulated for aquatic settings is required. Please note that aquatic herbicides are restricted for use in Washington State to licensed applicators only. 

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