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- Poaceae
- Poaceae Group 7
- Aristida
- Aristida basiramea
Aristida basiramea — fork-tipped threeawn
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Facts
Fork-tipped threeawn is found in open, sandy fields, grasslands, roadsides and disturbed areas. It is considered native to Maine, New Hampshire and Vermont, but not native to Massachusetts, where it also occurs.
Habitat
Anthropogenic (man-made or disturbed habitats), grassland, meadows and fields
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
-
- Maine
- Massachusetts
- New Hampshire
- Vermont
- Leaf blade width
- 1–1.5 mm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Spikelet length
- 7–8 mm
- Glume relative length
- one or both glumes are as long or longer than all of the florets
- Awn on glume
- the glume has an awn
- One or more florets
- there is one floret per spikelet
- Lemma awn length
- 10–15 mm
- 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
-
Flowers
- Anther number
- 3
- Awn on glume
- the glume has an awn
- Bristles below spikelets
- no
- Floret lower bract texture
- the lemma is hard and firm
- Floret number
- 1
- Floret types within spikelet
- all the florets within a spikelet are similar
- Glume awn length
- 1–2 mm
- Glume relative length
- one or both glumes are as long or longer than all of the florets
- Glume veins
- 1
- Glumes per spikelet
- 2
- Inflorescence arrangement
- the spikelets are uniform
- Inflorescence axis orientation
- the inflorescence axis is straight
- Inflorescence branch length
- Up to 2 cm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Inflorescence length
- 20–100 mm
- Inflorescence length to width ratio
- 2–5
- Inflorescence type (general)
- the spikelets are borne on stalks or on branches
- Inflorescence type (specific)
-
- the inflorescence is a raceme (a long unbranched stem with stalked flowers growing along it)
- the inflorescence is branched, and the branches do NOT both grow from the same side of the plant AND look like spikes
- Inflorescence width
- 10–20 mm
- Inforescence position
- the spikelets are mainly carried at the end of the stem
- Lemma awn base
- the awn is attached right at the tip of the lemma
- Lemma awn coiled
- the lemma awn is coiled at least one half turn
- Lemma awn length
- 10–15 mm
- Lemma awn number
- the lemma has more than one awn on it
- Lemma awn orientation
- the awn of the lemma on dried or older plants is curved or bent outwards
- Lemma base hairs
- the lemma has hairs at the base
- Lemma base length
- 0.4–0.6 mm
- 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
- Lower glume length
- 8–11 mm
- Lower glume relative length
- the lower glume is nearly as long, or as long as, the upper glume
- One or more florets
- there is one floret per spikelet
- Palea relative length
- palea is one half to fully as long as lemma
- Reproductive system
- all the flowers on the plant have both carpels and stamens (synoecious)
- Spikelet axis tip
- there is no extension of the spikelet axis beyond the tip of the spikelet
- Spikelet disintegration
- the spikelet breaks off above the glumes, so that after the florets fall off, the glumes remain
- Spikelet length
- 7–8 mm
- Spikelet number per node
- 0
- Spikelet position
- the spikelets emerge from both the upper and lower halves of the inflorescence branches
- Spikelets per panicle branch
- 1–3
- Spikelets spiny
- the spikelets do not appear spiny
- Tip of glume
- the tip of the glume is not divided (though it may have an awn on it)
- Upper glume length
- 10–12 mm
- Upper glume relative length
- the upper glume is more than one half as long as the lowest lemma
- Upper glume shape
- the upper glume is widest at or below the middle
-
Fruits or seeds
- Seed length
- 6–7 mm
-
Growth form
- Horizontal rooting stem
- no
- Lifespan
- the plant lives only a single year or less
- Rhizomes
- no
- Roots
- there are only slender roots on the plant
-
Leaves
- Basal leaves
- the plant has few or no leaves coming from the base of the flowering stem
- Leaf auricles
- the leaves do not have auricles
- Leaf basal lobe hairy
- NA
- Leaf blade cross-section
- the leaf blade is more or less flat in cross-section, or slightly folded or rolled inwards
- Leaf blade length
- 3–8 cm
- Leaf blade width
- 1–1.5 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 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
-
- Maine
- Massachusetts
- New Hampshire
- Vermont
- Specific habitat
-
- grasslands
- man-made or disturbed habitats
- meadows or fields
-
Stem, shoot, branch
- Plant height
- 25–45 cm
- Roots at lower stem nodes
- no
- Stem orientation
- the stems are upright
- Stem spacing
- the stems grow close together in compact clusters or tufts
Wetland status
Not classified
In New England
Distribution
- Connecticut
- absent
- Maine
- present
- Massachusetts
- present
- New Hampshire
- present
- Rhode Island
- absent
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Maine
- fairly widespread (S-rank: S4), special concern (code: SC)
- Massachusetts
- not applicable (S-rank: SNA)
- New Hampshire
- unrankable (S-rank: SU), Ind (code: Ind)
From Flora Novae Angliae dichotomous key
1. Aristida basiramea Engelm. ex Vasey n
Fork-tipped threeawn. MA, ME, NH, VT. Sandy, often sterile, soils of fields, grasslands, roadsides, and disturbed areas. Though this species is native to New England, it is considered non-native in MA.
Native to North America?
Yes and no (some introduced)
Sometimes confused with
- Aristida dichotoma:
- central awn 3-8 mm long and lateral awns 1-4 mm long, straight, and erect (vs. A. basiramea, with central awn 10-15 mm long and lateral awns 5-10 mm long, usually divergent from near the base).
- Aristida longespica:
- central awn not coiled at base and flowers either with 1 anther that is 0.2-0.3 mm long or 3 anthers that are 3-4 mm long (vs. A. basiramea, with central awn coiled at base 2 to 3 full turns and flowers with 3 anthers ca. 3 mm long).