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• Grass-like plants
• True grasses
• Dichanthelium commutatum

Dichanthelium commutatum — variable rosette-panicgrass

Facts

Ashe's variable rosette-panicgrass is native to southern and eastern North America, including New England, where it reaches the northeastern limit of its range. It grows in woodlands and sandy fields.

Habitat

Meadows and fields, woodlands

Characteristics

• Flowers

  Anther number

  0–3

  Awn on glume

  the glume has no awn

  Bristles below spikelets

  no

  Floret lower bract texture

  the lemma is hard and firm

  Floret number

  1–2

  Floret types within spikelet

  • NA
  • there are at least two distinct forms of florets within one spikelet

  Glume relative length

  • neither glume is quite as long as all of the florets
  • one or both glumes are as long or longer than all of the florets

  Glume shape

  the glume is flat or curved in cross-section

  Glume veins

  • 3
  • 5
  • 7 or more

  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

  Inflorescence length

  50–120 mm

  Inflorescence type (general)

  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 coiled

  NA

  Lemma awn length

  0 mm

  Lemma awn number

  the lemma has no awn

  Lemma awn orientation

  NA

  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

  • 3
  • 5
  • 7 or more

  One or more florets

  • there is more than one floret per spikelet
  • 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

  2.2–3.2 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

  Roots

  the plant has a root mass with a hardened top

• Leaves

  Basal leaves

  the plant has large or prominent tufts of leaves at the base of the flowering stem

  Leaf auricles

  the leaves do not have auricles

  Leaf blade base

  the leaf blade cuts in abruptly to the narrower base, or has rounded lobes on either side of the base (heart-shaped)

  Leaf blade width

  5–10 mm

  Leaf ligule length

  Up to 0.5 mm

  Leaf ligule type

  the leaf ligule is in the form of a membrane with 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 hair type

  • there are hairs on the surface of the leaf sheath, but the hairs do not have blisters at their bases
  • there are no hairs on the surface of the leaf sheath

  Leaf sheath hairs

  • there are hairs on the surface of the leaf sheath
  • there are no hairs on the surface of the leaf sheath

• Place

  Habitat

  terrestrial

  New England state

  • Connecticut
  • Massachusetts
  • Rhode Island

  Specific habitat

  • meadows or fields
  • woodlands

• Stem, shoot, branch

  Hairs at nodes

  • the stem nodes are hairless or they have very sparse hairs
  • the stem nodes have hairs that stand out at a shallow angle, or they curve downwards

  Stem hairs

  the stem has hairs on it

  Stem spacing

  the stems grow close together in compact clusters or tufts

Wetland status

Occurs in wetlands or non-wetlands. (Wetland indicator code: FAC)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae