Amphicarpum amphicarpon — Pursh's blue maidencane
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Facts
Pursh's blue maidencane was discovered in Nantucket, Massachusetts in 1988, 240 miles north of its previously known northernmost occurrence in New Jersey. The single population on a pond shore in Nantucket is vulnerable to changes in hydrology. This grass has two types of flowers, the aerial flowers producing conventional seeds, the underground flowers being self-fertile (chasmogamous), and producing a few larger, underground seeds.
Habitat
Shores of rivers or lakes
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.
enlargeCharacteristics
- Habitat
- wetlands
- New England state
- Massachusetts
- Leaf blade width
- 5–15 mm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Spikelet length
- 4–8 mm
- Glume relative length
- neither glume is quite as long as all of the florets
- Awn on glume
- 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
-
Flowers
- Anther number
- 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
- Glume shape
- the glume is flat or curved in cross-section
- Glumes per spikelet
- 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
- Inflorescence length
- 30–200 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)
- Lower glume length
- 0 mm
- Lower glume relative length
- NA
- 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
- 4–8 mm
-
Growth form
- Lifespan
- the plant lives only a single year or less
-
Leaves
- Leaf auricles
- the leaves do not have auricles
- Leaf blade width
- 5–15 mm
- Leaf ligule type
- the leaf ligule is in the form of fine hairs
- Leaf margin glands
- there are no glands along the edges of the leaf blade
- 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
- wetlands
- New England state
- Massachusetts
- Specific habitat
- shores of rivers or lakes
-
Stem, shoot, branch
- Stem spacing
- the stems grow singly or a few together (they may form diffuse colonies)
Wetland status
Usually occurs in wetlands, but occasionally in non-wetlands. (Wetland indicator code: FACW)
In New England
Distribution
- Connecticut
- absent
- Maine
- absent
- Massachusetts
- present
- New Hampshire
- absent
- Rhode Island
- absent
- Vermont
- absent
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Massachusetts
- extremely rare (S-rank: S1), endangered (code: E)
From Flora Novae Angliae dichotomous key
1. Amphicarpum amphicarpon (Pursh) Nash NC
Pursh’s blue maidencane. Amphicarpum purshii Kunth • MA; Nantucket Island. Coastal plain pond shores.