Pascopyrum smithii (Rydb.) A. Löve

western wheat grass

Copyright: various copyright holders. To reuse an image, please click it to see who you will need to contact.

New England Distribution

Adapted from BONAP data

Found this plant? Take a photo and post a sighting.

North America Distribution

Adapted from BONAP data

enlarge

Facts About

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)

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
Show All Characteristics
  • 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)

New England Distribution and Conservation Status

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
unranked (S-rank: SNR)

Native to North America?

Yes and no (some introduced)

Sometimes Confused With

Elymus repens

Synonyms

  • Agropyron smithii Rydb.
  • Elytrigia smithii (Rydb.) Nevski

Family

Poaceae

Genus

Pascopyrum

Need Help?

Get Help

Information from Dichotomous Key of Flora Novae Angliae

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.