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- Poaceae Group 5
- Elymus
- Elymus macgregorii
Elymus macgregorii — early wild-rye
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Facts
Early wild-rye is a rare but widespread grass confined to rich moist riparian floodplain and deciduous forests. This species is most likely to be confused with common eastern wild-rye (Elymus virginicus).
Habitat
Floodplain (river or stream floodplains), forests
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
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Leaf blade width
- 7–15 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
- 10–15 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 more than one floret per spikelet
- Lemma awn length
- 15–30 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
- 0.4–0.9 mm
- Anther length
- 2–4 mm
-
Flowers
- Anther length
- 2–4 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
- 2–4
- Floret types within spikelet
- there are at least two distinct forms of florets within one spikelet
- Glume awn length
- 10–25 mm
- Glume keel
- NA
- Glume relative length
- one or both glumes are as long or longer than all of the florets
- Glume shape
- the glume is flat or curved in cross-section
- Glume veins
-
- 3
- 5
- Glumes per spikelet
- 2
- Inflorescence arrangement
- the spikelets are uniform
- Inflorescence axis hairs
-
- the inflorescence axis is rough and feels like sand-paper
- the inflorescence axis is smooth and has no hairs
- Inflorescence axis orientation
- 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
- 40–120 mm
- Inflorescence length to width ratio
- 2.4–3
- 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
- 17–40 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
- 15–30 mm
- Lemma awn number
- the lemma has one awn on it
- Lemma awn orientation
- the awn of the lemma is straight
- Lemma hairs
- the lemma is hairless between the veins
- 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
- 7 or more
- Lemma vein orientation
- the veins on the lemma stay roughly parallel throughout
- Lower glume length
- 8–19 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 length
- 6–10 mm
- 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
- the spikelet breaks off below the glumes
- Spikelet length
- 10–15 mm
- Spikelet number per node
- Up to 3
- 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
- 8–19 mm
- Upper glume relative length
- the upper glume is more than one half as long as the lowest lemma
-
Fruits or seeds
- Groove on seed
- the caryopsis has a groove running most of its length
-
Growth form
- Horizontal rooting stem
- no
- Lifespan
- the plant lives more than two years
- 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 have auricles
- Leaf blade cross-section
- 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 width
- 7–15 mm
- Leaf ligule length
- 0.4–0.9 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 outward at more than a 45 degree angle from the stem, or it curves downwards from the horizontal
-
Place
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Vermont
- Specific habitat
-
- forests
- river or stream floodplains
-
Stem, shoot, branch
- Hairs at nodes
- the stem nodes are hairless or they have very sparse hairs
- Plant height
- 40–120 cm
- Stem node number
- 4–8
- 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
In New England
Distribution
- Connecticut
- present
- Maine
- present
- Massachusetts
- present
- New Hampshire
- present
- Rhode Island
- present
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Maine
- rare (S-rank: S2), special concern (code: SC)
- Massachusetts
- rare (uncertain) (S-rank: S2?)
- New Hampshire
- extremely rare (S-rank: S1), endangered (code: E)
- Rhode Island
- extremely rare (S-rank: S1), concern (uncertain) (code: C*)
- Vermont
- historical (S-rank: SH)
From Flora Novae Angliae dichotomous key
5. Elymus macgregorii R. Brooks & J.J.N. Campb. NC
early wild-rye. E. virginicus L. var. minor Vasey ex L.H. Dewey • CT, MA, ME, NH, RI, VT. Rich, mesic soils of high-terrace riparian floodplains and deciduous forests, often associated with Acer saccharum, Tilia americana, and/or Fraxinus americana.
Native to North America?
Yes
Sometimes confused with
- Elymus virginicus:
- glume awns 3-10 mm long and spikelets appressed (vs. E. macgregorii, with glume awns 10-25 mm long and spikelets loosely ascending).
- Elymus glabriflorus:
- spikes with 15–30 nodes separated by internodes 3–5 mm long and auricles 0-2 mm long (vs. E. macgregorii, with spikes 9–18 nodes separated by internodes 4–7 mm long and auricles 2-3 mm long).
Synonyms
- Elymus virginicus L. var. minor Vasey ex L.H. Dewey