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- Grass-like plants
- True grasses
- Agropyron cristatum
Agropyron cristatum — crested wheat grass
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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.
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Facts
Crested wheat grass is an exotic species originally introduced to the Great Plains and Intermountain regions to improve degraded pasture and rangelands. It is now considered a problematic weed, capable of forming large, monospecific stands that exclude native vegetation and reduce forage diversity. Crested wheatgrass is a rare visitor to New England, having been collected in Massachusetts and New Hampshire.
Habitat
Anthropogenic (man-made or disturbed habitats), meadows and fields
Characteristics
- Habitat
- terrestrial
- New England state
-
- Massachusetts
- New Hampshire
- Leaf blade width
- 1.5–6 mm
- Inflorescence branches
- there are no branch points between the base of the inflorescence axis and the flowers, or they are not obvious
- Spikelet length
- 7–16 mm
- Glume relative length
- neither glume is quite as long as all of the florets
- Awn on glume
- the glume has an awn
- One or more florets
- there is more than one floret per spikelet
- Lemma awn length
- 2–6 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
- Leaf ligule length
- Up to 1.5 mm
- Anther length
- 3–5 mm
-
Flowers
- Anther length
- 3–5 mm
- Anther number
- 3
- Awn on glume
- the glume has an awn
- Bristles below spikelets
- no
- Floret lower bract texture
- the lemma is thin and flexible
- Floret number
- 3–11
- Floret types within spikelet
- all the florets within a spikelet are similar
- Glume awn length
- 1–3 mm
- Glume keel
-
- the glume keels are rough or hairy
- the glume keels are smooth and hairless
- Glume relative length
- neither glume is quite as long as 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 hairs
- the inflorescence axis is hairy but not rough or sand-papery feeling
- 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
- 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
- 10–60 mm
- Inflorescence length to width ratio
- 1.3–2.4
- 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)
- Inflorescence width
- 8–25 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 straight or twisted, but not coiled one half turn
- Lemma awn length
- 2–6 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 V-shaped 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
-
- the keel of the lemma is hairless
- the keel of the lemma is rough, or has fine hairs
- 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)
- Lemma vein number
- 5
- Lemma vein orientation
- the veins on the lemma stay roughly parallel throughout
- Lower glume length
- 3–6 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
- 7–16 mm
- Spikelet number per node
- 1
- Spikelet pedicel
- the spikelets do not have pedicels
- Spikelet pedicel length
- 0 mm
- Spikelet position
- NA
- Spikelet shape
- 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
- 3–6 mm
- 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
-
Growth form
- Lifespan
- the plant lives more than two years
- Rhizomes
-
- no
- yes
-
Leaves
- Leaf auricles
- the leaves have auricles
- Leaf basal lobe hairy
- the lobes at the base of the leaf blades are hairless
- 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 hairy
- Leaf blade length
- 5–20 cm
- Leaf blade width
- 1.5–6 mm
- Leaf ligule length
- Up to 1.5 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
-
Place
- Habitat
- terrestrial
- New England state
-
- Massachusetts
- New Hampshire
- Specific habitat
-
- man-made or disturbed habitats
- meadows or fields
-
Stem, shoot, branch
- Hairs at nodes
- the stem nodes are hairless or they have very sparse hairs
- Plant height
- 20–110 cm
- Stem hairs
-
- the stem has hairs on it
- the stem is nearly to completely hairless
- Stem orientation
-
- the stems are upright
- the stems trail at the base, but turn upwards at the tips
- Stem spacing
- the stems grow close together in compact clusters or tufts
Wetland status
Not classified
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
- not applicable (S-rank: SNA)
Native to North America?
No
Sometimes confused with
- Agropyron desertorum:
- spikes 5-10 mm wide and spikelets diverging from the inflorescence rachis at an angle of 25-45 degrees (vs. A. cristatum, with spikes 8-23 mm wide and spikelets diverging from the inflorescence rachis at an angle of 45-90 degrees).
Synonyms
- Agropyron pectiniforme Roemer & J.A. Schultes
Family
Genus
From the dichotomous key of Flora Novae Angliae
1. Agropyron cristatum (L.) Gaert. E
crested wheat grass. Agropyron pectiniforme Roemer & J.A. Schultes • MA, NH. Fields, roadsides, waste places.