Scientific Name: Tripsacum dactyloides

Common Name: eastern gamagrass

Synonyms: Coix dactyloides

Habit: Eastern gamagrass is a perennial warm-season bunch type grass with large, thick rhizomes that may reach up to 6 ft in height.

Leaves: Leaf blades may reach 2 feet in length and 1 inch in width, and are rough to the touch but mostly without hairs except those that occur at the base of the upper leaf surfaces. Leaves lack auricles but have a ligule that is a fringe of hairs, approximately 1 to 1 1/2 mm in length. Ligules may be fused at the base taking on the appearance of a ligule that is both membranous and a fringe of hairs. The sheath is without hairs and is split at least part way up the stem with overlapping margins.

Identifying Characteristics: The large, thick rootstocks and relatively large leaves of this plant helps to distinguish it from almost any other grass. Additionally, the rather unique terminal seedhead is a good identifying characteristic of this species. Plants have very thick rootstocks, usually much larger than the width of the plant itself.

Flower Seed Head: Eastern Gamagrass has a conspicuous spike seed head that is 'jointed'. Seedheads (usually 1 to 3) are terminal spikes that are from 4 to 12 inches in length. Spikes consist of many tightly fused spikelets that eventually take on the appearance of being 'jointed'.

Where Found: It is native to most of the eastern part of the U.S. This grass is found from Massachusetts south to Florida. It is primarily a weed of pastures, hay fields, abandoned fields, roadsides, and along the edges of woods. It is most often grown for a forage crop. It does best in well drained soils.

  • Life cycle: perennial

  • Plant type: Grass

  • Auricle: not present

  • Plant family: Poaceae

  • Leaf arrangement: rolled in bud

  • Hair surface: hairs on basal half only

  • Ligule: hairy

  • Length: 1-2 mm

  • Seed head: spike

  • Width: more than 15 mm

  • Grass stem: round