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- Poaceae Group 5
- Pascopyrum
- Pascopyrum smithii
Pascopyrum smithii — western wheat grass
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Facts
Western wheat grass is a common grass of sagebrush grassland and pinyon-juniper woodland in the West, as well as Great Plains grasslands. An occasional visitor to New England, it has been collected in Massachusetts and New Hampshire railroads, roadsides and disturbed sites.
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
- 1–4.5 mm
- Inflorescence branches
-
- the flowers are attached to branches rather than to the main axis of the inflorescence
- there are no branch points between the base of the inflorescence axis and the flowers, or they are not obvious
- Spikelet length
- 12–30 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
- Lemma awn length
- 0.5–5 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
- Anther length
- 2.5–6 mm
-
Flowers
- Anther length
- 2.5–6 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
- 2–12
- Floret types within spikelet
- all the florets within a spikelet are similar
- Glume awn length
- 0 mm
- Glume keel
- NA
- 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
- Glume veins
-
- 3
- 5
- 7 or more
- Glumes per spikelet
- 2
- Inflorescence axis hairs
- the inflorescence axis is rough and feels like sand-paper
- Inflorescence axis orientation
-
- the inflorescence axis is arched or curved outward
- the inflorescence axis is straight
- Inflorescence branch length
- 0 cm
- Inflorescence branch roughness
- NA
- Inflorescence branches
-
- the flowers are attached to branches rather than to the main axis of the inflorescence
- there are no branch points between the base of the inflorescence axis and the flowers, or they are not obvious
- Inflorescence branches coming off the lowest stem node
- 0
- Inflorescence crowding
- NA
- Inflorescence length
- 50–170 mm
- Inflorescence type (general)
- the inflorescence is a spike, or is spike-like, lacking obvious branches
- Inflorescence type (specific)
- the inflorescence is a spike (a long unbranched stem with flowers along it that lack stalks)
- 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
-
- NA
- the lemma awn is straight or twisted, but not coiled one half turn
- Lemma awn length
- 0.5–5 mm
- Lemma awn number
-
- the lemma has no awn
- the lemma has one awn on it
- Lemma awn orientation
- the awn of the lemma is straight
- Lemma cross-section
- the lemma is flat or rounded if you cut across the midpoint
- Lemma hairs
-
- the lemma has fine hairs between the veins
- the lemma is hairless between the veins
- Lemma keel hairs
- NA
- Lemma marginal vein hairs
-
- the marginal vein of the lemma has fine hairs on it
- 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 is a simple point, with or without an awn (long narrow extension ending in a point)
- Lemma tip shape
-
- the lemma tip tapers to a long narrow point (it may or may not also have an awn or teeth at the tip)
- the lemma tip tapers to a narrow point (it may or may not also have an awn or teeth at the tip)
- Lemma vein number
-
- 5
- 7 or more
- Lemma vein orientation
- the veins on the lemma stay roughly parallel throughout
- Lower glume length
- 5–15 mm
- Lower glume relative length
-
- the lower glume is nearly as long, or as long as, the upper glume
- the lower glume is one third to three quarters 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 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
- 12–30 mm
- Spikelet number per node
- Up to 2
- Spikelet pedicel
- the spikelets do not have pedicels
- Spikelet pedicel length
- 0 mm
- Spikelet position
- NA
- Spikelet shape
-
- the spikelets are elliptic (widest in the middle, tapering to the ends) in profile
- the spikelets are oblong (rectangular, but with rounded ends) in profile
- Spikelets per panicle branch
- 0
- 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
- 5–15 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
- Groove on seed
- the caryopsis has a groove running most of its length
- Seed length
- 4–5 mm
-
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
- Basal leaves
- the plant has large or prominent tufts of leaves at the base of the flowering stem
- Leaf auricles
- the leaves have auricles
- 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 hairs
-
- the leaf blade is hairless, but it may have tiny prickles that give it a sand-papery feel
- the leaf blade is hairy
- Leaf blade length
- 2–26 cm
- Leaf blade texture
-
- the leaf blade is rough and sandpapery
- the leaf blade is smooth, or it may have soft hairs
- Leaf blade width
- 1–4.5 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 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
- Orientation of topmost leaf
- the flag leaf is held upright, or at less than a 45 degree angle out from the stem
-
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
- 20–100 cm
- 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
- 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
- absent
- Maine
- absent
- Massachusetts
- present
- New Hampshire
- present
- Rhode Island
- absent
- Vermont
- absent
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Massachusetts
- not applicable (S-rank: SNA)
From Flora Novae Angliae dichotomous key
1. Pascopyrum smithii (Rydb.) A. Löve E
western wheat grass. Agropyron smithii Rydb.; Elytrigia smithii (Rydb.) Nevski • MA, NH. Railroad rights-of-way, roadsides, disturbed soil.
Native to North America?
Yes and no (some introduced)
Sometimes confused with
- Elymus repens:
- glumes tapering from the apical third, unawned or somewhat abruptly tapering to an awn (vs. P. smithii, with the glumes gradually tapering from near midlength and +/- imperceptively passing into a short awn-tip).
Synonyms
- Agropyron smithii Rydb.
- Elytrigia smithii (Rydb.) Nevski