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• Elymus trachycaulus

Elymus trachycaulus — wheatgrass

Facts

Slender wild-rye is a widespread native of gravelly and ledgy river shores, cliffs and talus slopes, as well as open areas near the coast, and a range of wetlands. There are two subspecies recognized in New England. This versatile plant grows from Greenland to Mexico, and is introduced to Asia. Its forms are quite plastic -- forest-dwelling plants flower later and are more slender and tall than grassland-inhabiting forms. Its upright spikelets are tightly arrayed in a zig-zig up a long flowering stem.

Habitat

Bogs, cliffs, balds, or ledges, fens, forests, meadows and fields, ridges or ledges, shores of rivers or lakes, talus and rocky slopes, woodlands

Characteristics

• Flowers

  Anther length

  0.8–3 mm

  Anther number

  3

  Awn on glume

  • the glume has an awn
  • the glume has no awn

  Bristles below spikelets

  no

  Floret lower bract texture

  the lemma is thin and flexible

  Floret number

  3–8

  Floret types within spikelet

  there are at least two distinct forms of florets within one spikelet

  Glume awn length

  0–11 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
  • one or both glumes are as long or longer than all of the florets

  Glume veins

  • 3
  • 5
  • 7 or more

  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

  40–250 mm

  Inflorescence length to width ratio

  20–31.3

  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

  2–8 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

  0–24 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
  • the awn of the lemma on dried or older plants is curved or bent outwards

  Lemma hairs

  the lemma is hairless between the veins

  Lemma keel hairs

  • NA
  • 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 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 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

  5–17 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

  7–9 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

  Spikelet length

  9–20 mm

  Spikelet number per node

  At least 1

  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

  Spikelet width

  3–6 mm

  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

  5–17 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 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
  • yes

  Roots

  • the plant has rhizomes (horizontal underground stem with roots growing from it)
  • 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
  • the plant has large or prominent tufts of leaves at the base of the flowering stem

  Leaf auricles

  • the leaves do not have 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

  Up to 20 cm

  Leaf blade texture

  the leaf blade is smooth, or it may have soft hairs

  Leaf blade width

  2–8 mm

  Leaf ligule length

  0.2–0.8 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
  • the flag leaf is held upright, or at less than a 45 degree angle out from the stem

• Place

  Habitat

  • terrestrial
  • wetlands

  New England state

  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont

  Specific habitat

  • bogs
  • cliffs, balds, or ledges
  • fens
  • forests
  • meadows or fields
  • ridges or ledges
  • shores of rivers or lakes
  • talus or rocky slopes
  • woodlands

• Stem, shoot, branch

  Hairs at nodes

  • the stem nodes are hairless or they have very sparse hairs
  • the stem nodes have hairs that stand out at a shallow angle, or they curve downwards

  Plant height

  30–150 cm

  Stem hairs

  • the stem has hairs on it
  • 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

From the dichotomous key of Flora Novae Angliae