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- Poaceae
- Poaceae Group 10
- Panicum
- Panicum amarum
Panicum amarum — bitter panicgrass
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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
New England distribution
Adapted from BONAP data
Native: indigenous.
Non-native: introduced (intentionally or unintentionally); has become naturalized.
County documented: documented to exist in the county by evidence (herbarium specimen, photograph). Also covers those considered historical (not seen in 20 years).
State documented: documented to exist in the state, but not documented to a county within the state. Also covers those considered historical (not seen in 20 years).
Note: when native and non-native populations both exist in a county, only native status is shown on the map.
Found this plant? Take a photo and post a sighting.
Characteristics
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Massachusetts
- Leaf blade width
- 2–13 mm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Spikelet length
- 4–7.7 mm
- Glume relative length
- both glumes are as long or longer than all of the florets
- Awn on glume
-
- the glume has an awn
- the glume has no awn
- One or more florets
-
- there is more than one floret per spikelet
- there is one floret per spikelet
- Lemma awn length
- 0 mm
- Leaf sheath hair type
- there are no hairs on the surface of the leaf sheath
- Leaf ligule length
- 1–5 mm
-
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)
In New England
Distribution
- Connecticut
- present
- Maine
- absent
- Massachusetts
- present
- New Hampshire
- absent
- Rhode Island
- present
- Vermont
- absent
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Connecticut
- rare (S-rank: S2), threatened (code: T)
- Massachusetts
- unranked (S-rank: SNR)
ssp. amarum
- Rhode Island
- extremely rare (S-rank: S1), concern (uncertain) (code: C*)
From Flora Novae Angliae dichotomous key
1. Panicum amarum Ell. nC
bitter panicgrass. 1a. Panicum amarulum A.S. Hitchc. & Chase; P. amarum Ell. var. amarulum (A.S. Hitchc. & Chase) P.G. Palmer • CT, MA, RI. Atlantic coast beaches, dunes, sandy roadsides.
1a. Lower glume with 3–5 veins, the midvein smooth apically; spikelets 4–5.9 mm long; panicles with 2 or more primary branches per node; rhizomes short and/or ascending; reproductive stems often cespitose, mostly 100–250 cm tall
… 1a. P. amarum ssp. amarulum (A.S. Hitchc. & Chase) Freckmann & Lelong
1b. Lower glume with 7–9 veins, the midvein minutely scabrous apically; spikelets 4.7–7.7 mm long; panicles with 1 or 2 primary branches per node; rhizomes horizontally elongate; reproductive stems usually solitary, mostly 20–150 cm tall … 1b. P. amarum ssp. amarum
Subspecies amarulum is known from CT, MA and is considered non-native (original populations are believed to have been intentionally introduced). Subspecies amarum is known from CT, RI. It is both native and of conservation concern.
Native to North America?
Yes