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- Dichotomous Key
- Poaceae
- Poaceae Group 3
- Deschampsia
- Deschampsia danthonioides
Deschampsia danthonioides — annual hair grass
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Facts
Annual hair grass is a species of western North America, and a rare visitor to New England, having been collected only from the dump sites of nineteenth-century wool-carding factories in Maine.
Habitat
Anthropogenic (man-made or disturbed habitats)
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
- Leaf blade width
- 0.3–1.5 mm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Spikelet length
- 4–9 mm
- Glume relative length
- one or both glumes are as long or longer than all of the florets
- Awn on glume
- the glume has no awn
- One or more florets
- there is more than one floret per spikelet
- Lemma awn length
- 4–9 mm
- Leaf sheath hair type
- there are no hairs on the surface of the leaf sheath
- Leaf ligule length
- 0.5–4.7 mm
- Anther length
- 0.3–0.5 mm
-
Flowers
- Anther length
- 0.3–0.5 mm
- Anther number
- 3
- Awn on glume
- the glume has no awn
- Bristles below spikelets
- no
- Floret lower bract texture
- the lemma is thin and flexible
- Floret number
- 2–3
- Floret types within spikelet
- all the florets within a spikelet are similar
- Glume awn length
- 0 mm
- Glume relative length
- one or both glumes are as long or longer than all of the florets
- Glume shape
- the glume is V-shaped in cross-section
- Glume veins
- 3
- Glumes per spikelet
- 2
- Inflorescence arrangement
- the spikelets are uniform
- Inflorescence axis orientation
-
- the inflorescence axis is arched or curved outward
- the inflorescence axis is straight
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Inflorescence crowding
-
- the panicle is somewhat to very congested (crowded), and the branches may not be clearly seen without close inspection
- the panicle is somewhat to very spread out, with clearly-evident branches
- Inflorescence length
- 50–250 mm
- Inflorescence length to width ratio
- 2.5–3.2
- 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
- Inflorescence width
- 20–80 mm
- Inforescence position
- the spikelets are mainly carried at the end of the stem
- Lemma awn base
-
- the awn is attached at the lower half of the lemma (it emerges from near the base of the lemma)
- the awn is attached at the upper half of the lemma
- Lemma awn coiled
- the lemma awn is straight or twisted, but not coiled one half turn
- Lemma awn length
- 4–9 mm
- Lemma awn number
- the lemma has one awn on it
- Lemma awn orientation
- the awn of the lemma on dried or older plants is curved or bent outwards
- Lemma base hair length
- 0.4–1.6 mm
- Lemma base hairs
- the lemma has hairs at the base
- Lemma cross-section
- the lemma is flat or rounded if you cut across the midpoint
- Lemma hairs
- the lemma is hairless between the veins
- Lemma keel hairs
- NA
- Lemma marginal vein hairs
- the marginal vein of the lemma is hairless
- Lemma surface
- the surface of the lemma is relatively smooth (not counting any longitudinal veins or hairs)
- Lemma tip
-
- the lemma tip has a ragged edge
- the lemma tip is split into two or more points
- Lemma tip shape
-
- the lemma tip is rounded off or truncate (ends abruptly in a more or less straight line as though cut off); it may or may not also have an awn or teeth at the tip
- the lemma tip tapers to a broad point (it may or may not also have an awn or teeth at the tip)
- Lemma vein number
- 5
- Lower glume length
- 4–9 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 more than 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 an 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
- 4–9 mm
- Spikelet number per node
- Up to 0
- Spikelet pedicel
- the spikelets have pedicels
- Spikelet position
- the spikelets emerge mainly from the upper halves of the inflorescence branches
- Spikelet shape
- the spikelets are obtriangular (triangular, with the widest end away from the point of attachment) in profile
- 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
- 3.5–8.5 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
-
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 large or prominent tufts of leaves at 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 clearly folded or rolled inwards
- the leaf blade is more or less flat in cross-section, or slightly folded or rolled inwards
- Leaf blade width
- 0.3–1.5 mm
- Leaf ligule length
- 0.5–4.7 mm
- Leaf ligule type
- the leaf ligule is in the form of a membrane
- 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 color and persistence
- the leaf sheathes are off-white to light-brown and mostly persist in older leaves
- 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
- Maine
- Specific habitat
- man-made or disturbed habitats
-
Stem, shoot, branch
- Hairs at nodes
- the stem nodes are hairless or they have very sparse hairs
- Plant height
- 10–70 cm
- Roots at lower stem nodes
- no
- Stem hairs
- the stem is nearly to completely hairless
- 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
- absent
- New Hampshire
- absent
- Rhode Island
- absent
- Vermont
- absent
Conservation status
None
From Flora Novae Angliae dichotomous key
3. Deschampsia danthonioides (Trin.) Munro E
annual hair grass. Aira danthonioides Trin. • ME. Wool waste, edges of lawns.
Native to North America?
Yes and no (some introduced)
Sometimes confused with
- Deschampsia elongata:
- panicles congested, with appressed branches, lemma awns straight or slightly bent, and plants perennial (vs. D. danthonioides, with panicles contracted to open, with erect to ascending branches, lemma awns strongly bent, and plants annual).
Synonyms
- Aira danthonioides Trin.