Japanese Stilt Grass
FULL SCIENTIFIC NAME
Microstegium vimineum (Trin.) A. Camus
FAMILY NAME COMMON
FAMILY SCIENTIFIC NAME
Synonyms: Eulalia viminea (Trin.) Kuntze
Microstegium vimineum is an annual grass that can grow up to 2 m (6.5 ft.) tall. Its culms root at the nodes forming long, branched, prostrate or reclining stems up to 1.52 m (5 ft.) in length with numerous upright branches resembling individual plants. Both the nodes and internodes are glabrous. The alternate light green leaves are 5-8 cm (2-3 in.) long and up to 15 mm wide. They are lanceolate in shape and taper at both ends. Both upper and lower leaf surfaces are slightly pubescent, except for the silvery line running down the center of the blade. The summit of the leaf sheath collar is ciliate on one or both sides; the membranous ligule is also ciliate. The inflorescence is a terminal, thick-branched panicle 2-7 cm (0.8-2.8 in.) in length, barely if at all exerted from sheathing leaves. It has fewer than five branches, usually only one or two. The spikelets are paired and deciduous. Glumes are present and awnless. The lemmas, two per spikelet, can be awned or awnless although most northeastern specimens appear awned. The 3 mm (0.1 in.) ellipsoid fruit, a caryopsis (grain), ranges from yellow to yellow-purple in color, changing with the season. Microstegium vimineum begins to flower in mid-September. It fruits from late September through early October producing an abundant crop of caryopses. Many of these appear to germinate, giving rise to dense stands of light-green individuals. In late fall, Microstegium fades to pale greenish-yellow or turns pale-purple in color. Page References: Gleason & Cronquist 815, Holmgren 772, Magee & Ahles 191. See reference section below for full citations.
Leersia virginica Willd. (White grass) Microstegium vimineum is easily confused with Leersia virginica, the native white grass. The following table compares the characteristics of these two species.
Microstegium vimineum is mechanically dispersed. Long distance dispersal may occur by clinging to animals and people.
Microstegium vimineum is native to tropical Asia. In the United States, it is has been reported from New York to Florida, and west to Illinois, Arkansas, Louisiana and Texas. It has also been reported from Puerto Rico. In New England it is present in Connecticut and Massachusetts.
HISTORY OF INTRODUCTION IN NEW ENGLAND
Since its initial report from Tennessee in 1919, where it was thought to have been used as packing material, Microstegium vimineum has spread rapidly northward, reaching southern New England by the 1980s. The first Connecticut report came from Branford in 1984. This plant was reported from Hamden County, Massachusetts in 1998 and from a few localities in Rhode Island in 2005.
HABITATS IN NEW ENGLAND
Abandoned Field, Early Successional Forest, Edge, Floodplain Forest, Forest Wetland, Herbaceous Wetland, Late Successional Forest, Planted Forest, Railroad Right-of-Way, Roadside, Shrub Wetland, Utility Right-of-Way, Vacant Lot, Wet Meadow, Yard or Garden. Microstegium vimineum easily invades disturbed areas and has the ability to produce seeds in low light, thus allowing it to thrive in shade. In New England, Microstegium vimineum has invaded floodplain forests, early and late successional forests, abandoned fields, roadsides and other habitats.
Microstegium vimineum forms dense monotypic stands that can dominate entire habitats, including the understory of a forest. These dense stands displace native understory and wetland vegetation. The fact that this plant can grow in low light threatens not only "edge" communities, but forests as well. Each plant produces many seeds that can persist in the seed bank for long periods of time. Even if an area is burned Microstegium seeds will sprout up, making control of large populations difficult. The seeds are easily spread by hikers by attaching to their clothing.
Virginia Department of Conservation and Recreation - A fact sheet containing information about the species as well as some control measures.
Plant Conservation Alliance - Fact sheet includes management information
Documentation required: Herbarium specimen or mounted snippet of the stems with inflorescences. Best time for documentation: Fall.
Integrated Taxonomic Information System - Has general taxonomic information about the species.
The PLANTS Database - Distribution information and additional links
Virginia Department of Conservation and Recreation - General information
North Carolina State University - A fact sheet
Plant Conservation Alliance - Fact Sheet
Barden, L.S. 1987. Invasion Of Microstegium Vimineum (Poaceae), An Exotic, Annual, Shade-Tolerant, C4 Grass, Into A North Carolina Floodplain. American Midland Naturalist 118: 40-45.
Benedict, J., G. Spyreas, D.J. Gibson. 2001. Survivorship and individual attributes of Microstegium vimineum in relation to environmental variables. Transactions of the Illinois State Academy of Science 94 (Supplement): 52.
Ehrenfeld, J.G. 1999. A Rhizomatous, Perennial Form Of Microstegium Vimineum (Trin.) A-Camus In New Jersey. Journal Of The Torrey Botanical Society 126 (4): 352-358.
Fairbrothers, D.E., and Gray, J.R. (1972) Microstegium vimineum (Trin.) A. Camus (Graminaceae) in the United States. Bulletin of the Torrey Botanical Club 99, 97-100.
Gleason H.A. and A.C. Cronquist. 1991. Manual of Vascular Plants of the Northeastern United States and Adjacent Canada. 2nd ed. New York Botanical Garden, Bronx, New York.
Gibson, D.J., Spyreas, G., and Benedict, J. (2002) Life History of Microstegium vimineum (Poaceae) an invasive grass in Illinois. Journal of the Torrey Botanical Society129, 207-219.
Holmgren N.H. 1998. Illustrated Companion to Gleason and Cronquist's Manual. New York Botanical Garden, Bronx, New York.
Horton, J.L. and H.S. Neufeld. 1998. Photosynthetic Responses Of Microstegium Vimineum (Trin.) A. Camus, A Shade-Tolerant, C4 Grass, To Variable Light Environments. Oecologia 114: 11-19.
Hunt, D.M. and R.E. Zaremba. 1992. The Northeastward Spread Of Microstegium Vimineum (Poaceae) Into New York And Adjacent States. Rhodora 94(878): 167-170.
Invasive Alien Plant Species Of Virginia: Japanese Stilt Grass (Microstegium Vimineum). Virginia Native Plant Society. VA NHP Japanese Stilt Grass Fact Sheet. 2000. Http://Vnps.Org/Invasive/FSMICROS.Html.
Kourtey, P.S., J.G. Ehrenfeld and W.Z. Huang. 1998. Effects Of Exotic Plant Species On Soil Properties In Hardwood Forests Of New Jersey. Water Air And Soil Pollution. 105 (1-2): 493-501.
Lafleur, A. Invasive Plant Information Sheet: Japanese Stilt Grass. The Nature Conservancy, Connecticut Chapter, Hartford, CT.1996
Loope, L.L (1992) An overview of problems with introduced plant species in Nation Parks and biosphere reserves of the United States. In: Stone, C.P., Smith, C.W., and Tunison, JT (eds) Alien plant invasions in native ecosystems of Hawaii. University of Hawaii Press, Honolulu, pp. 3-28
Magee D.W and H.E. Ahles. 1999. Flora of the Northeast. University of Massachusetts Press, Amherst.
Mehrhoff, L.J. 2000. Perennial Microstegium Vimineum (Poaceae): An Apparent Misidentification? Journal Of The Torrey Botanical Society 127 (3): 251-254.
Orwig, D.A. and D.R. Foster. 1998. Forest Response To The Introduced Hemlock Woolly Adelgid In Southern New England, USA. Journal Of The Torrey Botanical Society 125 (1): 60-73.
Redman, D.E. 1995. Distribution And Habitat Types For Nepal Microstegium [Microstegium Vimineum (Trin.) Camus] In Maryland And The District Of Columbia. Castanea 60(3): 270-275.
Woods, F.W. 1989. Control Of Paulownia Tomentosa And Microstegium Vimineum In National Parks. A Report To The Great Smoky Mountains National Park.