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- Elymus wiegandii
Elymus wiegandii — Wiegand's wild-rye
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Facts
Wiegand's wild-rye inhabits riparian forests, usually on rich soils. It is found throughout New England, except for Rhode Island. It is a prairie grass of northern climes, coming close to the edge of its range in New England. It can be confused with Elymus canadensis, but it is more robust and its leaves are broader than that species. It flowers from mid-July to early August. The species name honors the famous botanist, Karl M. Weigand (1873-1942), who led the Cornell herbarium (Bailey Hortatorium) for 28 years and vastly increased its plant collections to over 250,000 specimens.
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
- Vermont
- Leaf blade width
- 8–25 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
- 12–20 mm
- Glume relative length
-
- neither glume is quite as long as all of the florets
- 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
- Up to 1 mm
- Anther length
- 2–3.5 mm
-
Flowers
- Anther length
- 2–3.5 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
- 3–7
- Floret types within spikelet
- there are at least two distinct forms of florets within one spikelet
- Glume awn length
- 5–18 mm
- Glume keel
- NA
- Glume relative length
-
- neither glume is quite as long as all of the florets
- 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
-
- 1
- 3
- 5
- 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
- the inflorescence axis is smooth and has no hairs
- Inflorescence axis orientation
- the inflorescence axis bends downwards or hangs
- 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
- 100–300 mm
- Inflorescence length to width ratio
- 3.3–6
- 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
- 30–50 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 on dried or older plants is curved or bent outwards
- 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
- Lemma vein orientation
- the veins on the lemma stay roughly parallel throughout
- Lower glume length
- 7–13 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
- 9–14 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
- 12–20 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
- 7–13 mm
- Upper glume relative length
- the upper glume is up to one half as long as the lowest lemma
- Upper glume shape
-
- the upper glume is widest above the middle
- 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
- 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 length
- 20–35 cm
- Leaf blade width
- 8–25 mm
- Leaf ligule length
- Up to 1 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
- 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
- 100–220 cm
- Stem node number
- 9–16
- Stem orientation
- the stems are upright
- Stem spacing
- the stems grow close together in compact clusters or tufts
Wetland status
Occurs in wetlands or non-wetlands. (Wetland indicator code: FAC)
In New England
Distribution
- Connecticut
- present
- Maine
- present
- Massachusetts
- present
- New Hampshire
- present
- Rhode Island
- absent
- Vermont
- present
Conservation status
Exact status definitions can vary from state to state. For details, please check with your state.
- Connecticut
- rare (S-rank: S2), special concern (code: SC)
- Massachusetts
- fairly widespread (uncertain) (S-rank: S4?)
- Vermont
- uncommon (S-rank: S3)
From Flora Novae Angliae dichotomous key
11. Elymus wiegandii Fern. N
Wiegand’s wild-rye. Elymus canadensis L. var. wiegandii (Fern.) Bowden • CT, MA, ME, NH, VT. Riparian forests, usually on rich soils of high terraces.
7×11. Elymus riparius × Elymus wiegandii → This very rare wild-rye hybrid is known from VT. It is largely sterile (as shown by its abortive pollen) and on the surface appears to be a less robust, narrower-leaved form of Elymus wiegandii (i.e., it often has the conspicuously drooping spikes of that species). However, the hybrid plants show spikelets with mostly 2 or 3 florets, indurate and usually unstriate glume bases, and paleas mostly 10–10.5 mm long (with nodding or arching spikes, spikelets with mostly 2 florets, indurate and unstriate glume bases, and paleas 6–9 mm long in E. riparius vs. conspicuously drooping spikes, spikelets with mostly 4–6 florets, slightly indurate and somewhat striate glume bases, and paleas 9–14 mm long in E. wiegandii).
Native to North America?
Yes
Sometimes confused with
- Elymus canadensis:
- leaf blades minutely scabrous on the adaxial surface, 3-15 mm wide, glumes 0.5-1.6 mm wide, and inflorescence erect to arching (vs. E. wiegandii, with leaf blades short-pilose on the adaxial surface, mostly 15-25 mm wide, glumes 0.3-0.8 mm wide, and inflorescence conspicuously drooping from the near the base).
Synonyms
- Elymus canadensis L. var. wiegandii (Fern.) Bowden