Japanese stiltgrass

Microstegium vimineum

Common names:
Japanese stiltgrass, Asian stiltgrass, Chinese packing grass, Japanese grass, Nepal Microstegium, flexible sesagrass, Mary’s grass, Nepalgrass, Basketgrass, Nepalese browntop

Problem Plant

Japanese stiltgrass (Microstegium vimineum) is an exotic weed in Illinois. The Illinois Exotic Weed Act prohibits the sale or distribution of this plant in Illinois. It is an annual grassy weed.

Each plant can produce large quantities of seeds. This high rate of seed production, coupled with the plant’s ability to tolerate shade and wet sites, has allowed it to out compete native woodland plants. Japanese stiltgrass commonly grows in wetlands and moist woodlands. It can also be found in disturbed sites, ditches, rights of way and even in landscape beds. This weed was accidentally introduced from Asia. It is now found throughout a number of states in the eastern half of the United States.

There are a number of native and nonnative species that could be used in place of Japanese stiltgrass. More desirable species may be found using the Search Trees and Plants page of the Arboretum website.Before purchasing or planting, be sure to check for any local or state guidelines on this species, and make sure that this plant is suitable for its habitat by checking its attributes at mortonarb.org or plants.usda.gov.

More Information

Size and Method of Spreading

Japanese stiltgrass is an annual grass with a prostrate, sprawling habit, and can grow from 6 inches to 3 feet tall. It spreads readily by seed.

Leaf Description

The leaves are simple and alternate. The leaf blades can be up to 4 inches long and ½ inch wide, with entire edges (margins) and a silvery, off-center midrib. The leaves bear some resemblance to bamboo leaves.

Flower Description

The small, wind-pollinated flowers are borne in spike-like clusters at the end of the stem (culm). Some of the flowers can self-fertilize and produce seeds before opening, increasing the potential for seed production.