Japanese stilt grass leaves

Japanese stilt grass (Microstegium vimineum)

Annual grass that is generally 1-3’ tall but will also spread in a mat-like manner. The stems are hairless and branched with upward pointing tips. Japanese stilt grass can spread vegetatively by rooting at the nodes as well as by seed.

Overview

Regulated areas of Japanese stilt grass
Japanese stilt grass is Prohibited (Red counties)

Other names for this plant include:

  • Common names: Nepalese browntop, Chinese packing grass, bamboograss
  • Scientific names: Eulalia viminea; M. aristulatum

Ecological threat:

  • Prefers wetlands, streambanks, ditches, mesic forests, floodplains where its large seed bank can be spread by moving water.
  • Out-competes native plants in low light conditions.

Classification in Wisconsin: Prohibited

Species Assessment Groups (SAG) were assembled to recommend a legal classification for each species considered for NR 40. The recommendation for Japanese stilt grass was based upon this literature review developed by the department.

Identification

Leaves: Alternate, lance-shaped leaves that taper at both ends, are 2-3” long, and pale green with a silvery stripe down the midvein that is slightly off center. Foliage turns purplish in the fall.

Flowers: There are several 1-3” long flower spikes that appear either terminally or in the leaf axils. Spikelets are hairy and the flowers bloom starting in mid-September.

Fruits & seeds: Can produce up to 1,000 seeds during a growing season with seeds remaining viable for 3-5 years.

Roots: Shallow fibrous roots.

Similar species: Whitegrass or Virginia cutgrass (Leersia virginica; native) lacks the silver stripe along midrib and has flower spikes that occur in August which is earlier than stilt grass. The leaf nodes of whitegrass are hairy the foliage stays green into the fall. Stilt grass has non-hairy leaf nodes and the foliage turns purple in fall.

Distribution

Known county distribution of Japanese stilt grass
Counties in WI where Japanese stilt grass has been reported (as of July 2011). Both vouchered and unvouchered reports included.

Currently, there have not been reports of Japanese stilt grass in WI. Have you seen it? Send us a report.

Control

Mechanical: Can hand pull small populations or mow at peak bloom before seeds set.

Chemical: Glyphosate or grass specific herbicide will work; in dry areas, imazipic plus MSO can be applied pre- or –post-emergent.

Photos

View Japanese stilt grass pictures in our photo gallery!

Resources

Sources for content:

  • Czarapata, Elizabeth; Invasive Plants of the Upper Midwest: an illustrated guide to their identification and control. University of Wisconsin Press. 2005. Pg. 141-142

Links for More Information

Last revised: Wednesday December 19 2012