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Weed Identification

Nepalese browntop

Family

Poaceae

Scientific Name

Microstegium vimineum

Other Common Names:

Japanese grass
Japanese stilt grass
Mary's grass
Nepalgrass

Synonyms (former Scientific Names):

Andropogon vimineum
Eulalia viminea
Eulalia viminea var. variabilis
Microstegium vimineum

Habit

Japanese Stiltgrass occurs on stream banks, river bluffs, floodplains, emergent and forested wetlands, moist woodlands, early successional fields, uplands, thickets, roadside ditches, gas and power line corridors and home lawns and gardens. It appears to be associated primarily with moist, acidic to neutral soils that are high in nitrogen. Plants are often found in moist shade or dry open areas. Plants germinate slightly before typical crabgrass germination (February in the deep south and April in the Transition Zone). Sporadic germination can continue at any time during the growing season. Plants die with cold temperatures in the fall.

Leaves

Its thin, pale green, lance-shaped, about 3 inches in length, alternate along a branched stalk and have a silvery stripe of reflective hairs down the middle of the upper leaf surface.

Identifying Characteristics

Stiltgrass readily invades disturbed shaded areas like floodplains that are prone to natural scouring, and areas subject to mowing, tilling and other soil disturbing activities.

Flower Seed Head

Seedheads are erect, thin, spike-like racemes. Delicate spikes of flowers emerge from slender tips beginning in September and continuing until Frost.

Seed Fruit

It spreads by seed and each plant can produce an estimated 100-1,000 seeds. Once established at a site, seed stored in the soil have been documented to persist for three to six years.

Where Found

Japanese stilt grass is currently established in sixteen eastern states, from New York to Florida. It is also found in Japan, Korea, China, Malaysia and India.

Leaf Hair on Upper Surface

hairs from base to tip

Leaf Arrangement

rolled in bud

Mature Leaf Width

6 to 15 mm

Stem

round

Seedhead

spike

Life Cycle

summer annual

Auricle

not present

Ligule

membrane

Ligule Length

less than 1 mm

Plant Type

Grass