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• True grasses
• Sporobolus compositus

Sporobolus compositus — rough dropseed

Facts

Widespread in the Great Plains and Midwest, rough dropseed is rare in New England. It occurs on a variety of open habitats, mostly with sandy substrates. As with other grassland species, the apparent decline of rough dropseed in New Enlgland may be due to widespread reforestation since the late nineteenth century. There are two varieties present in New England, both of conservation concern. One of them (Sporobolus compositus var. compositus) is found in Connecticut, Massachusetts, Rhode Island and Vermont, while the other (S. compositus var. drummondii) is found only in Maine.

Habitat

Anthropogenic (man-made or disturbed habitats), cliffs, balds, or ledges, coastal beaches (sea beaches), forest edges, grassland, meadows and fields, ridges or ledges, shores of rivers or lakes, talus and rocky slopes

Characteristics

• Flowers

  Anther length

  1–2 mm

  Anther number

  2–3

  Awn on glume

  the glume has no awn

  Floret lower bract texture

  the lemma is thin and flexible

  Floret types within spikelet

  all the florets within a spikelet are similar

  Glume relative length

  neither glume is quite as long as all of the florets

  Glume veins

  • 0
  • 1

  Inflorescence arrangement

  the spikelets are uniform

  Inflorescence axis orientation

  the inflorescence axis is straight

  Inflorescence branches

  • the flowers are attached to branches rather than to the main axis of the inflorescence
  • there are no branch points between the base of the inflorescence axis and the flowers, or they are not obvious

  Inflorescence length

  50–300 mm

  Inflorescence type (general)

  • the inflorescence is a spike, or is spike-like, lacking obvious branches
  • the spikelets are borne on stalks or on branches

  Inflorescence type (specific)

  the inflorescence is branched, and the branches do NOT both grow from the same side of the plant AND look like spikes

  Lemma awn base

  NA

  Lemma awn length

  0 mm

  Lemma awn number

  the lemma has no awn

  Lemma cross-section

  the lemma is flat or rounded if you cut across the midpoint

  Lemma surface

  the surface of the lemma is relatively smooth (not counting any longitudinal veins or hairs)

  Lemma tip

  the lemma tip is a simple point, with or without an awn (long narrow extension ending in a point)

  Lemma vein number

  1

  One or more florets

  there is one floret per spikelet

  Palea relative length

  palea is one half to fully as long as lemma

  Spikelet axis tip

  there is no extension of the spikelet axis beyond the tip of the spikelet

  Spikelet length

  4–10 mm

  Spikelets spiny

  the spikelets do not appear spiny

  Upper glume shape

  the upper glume is widest at or below the middle

• Growth form

  Lifespan

  the plant lives more than two years

• Leaves

  Leaf auricles

  the leaves do not have auricles

  Leaf blade width

  1.5–10 mm

  Leaf ligule length

  0.1–0.5 mm

  Leaf ligule type

  the leaf ligule is in the form of fine hairs

  Leaf sheath closed around stem

  the margins of the leaf sheath are overlapping and not fused together except in the basal half (or less)

  Leaf sheath hairs

  there are hairs on the surface of the leaf sheath

• Place

  Habitat

  • terrestrial
  • wetlands

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • Rhode Island
  • Vermont

  Specific habitat

  • cliffs, balds, or ledges
  • edges of forests
  • grasslands
  • man-made or disturbed habitats
  • meadows or fields
  • ridges or ledges
  • sea beaches
  • shores of rivers or lakes
  • talus or rocky slopes

• Stem, shoot, branch

  Stem spacing

  • the stems grow close together in compact clusters or tufts
  • the stems grow singly or a few together (they may form diffuse colonies)

  Stem thickness at base

  1–5 mm

Wetland status

Not classified

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae