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• Dichotomous Key
• Poaceae
• Poaceae Group 10
• Panicum
• Panicum amarum

Panicum amarum — bitter panicgrass

Facts

Bitter panicgrass inhabits beaches, dunes and sandy roadsides along the coast. There are two subspecies in New England. One (Panicum amarum ssp. amarum) is an endangered species from Connecticut and Rhode Island, while the other (P. amarum ssp. amarulum) is introduced, and found in Connecticut and Massachusetts.

Habitat

Anthropogenic (man-made or disturbed habitats), coastal beaches (sea beaches), dunes

Characteristics

• Flowers

  Anther number

  3

  Awn on glume

  • the glume has an awn
  • 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

  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 branches coming off the lowest stem node

  At least 1

  Inflorescence crowding

  the panicle is somewhat to very congested (crowded), and the branches may not be clearly seen without close inspection

  Inflorescence length

  100–800 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

  4–7.7 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

  Rhizomes

  yes

  Roots

  the plant has rhizomes (horizontal underground stem with roots growing from it)

• Leaves

  Leaf auricles

  the leaves do not have auricles

  Leaf blade hairs

  the leaf blade is hairless, but it may have tiny prickles that give it a sand-papery feel

  Leaf blade width

  2–13 mm

  Leaf ligule length

  1–5 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 no hairs on the surface of the leaf sheath

  Leaf sheath hairs

  there are no hairs on the surface of the leaf sheath

• Place

  Habitat

  terrestrial

  New England state

  • Connecticut
  • Massachusetts

  Specific habitat

  • dunes
  • man-made or disturbed habitats
  • sea beaches

• Stem, shoot, branch

  Hairs at nodes

  the stem nodes have hairs that stand out at a shallow angle, or they curve downwards

  Plant height

  20–250 cm

  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)

Wetland status

Usually occurs in non-wetlands, but occasionally in wetlands. (Wetland indicator code: FACU)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae