Agrostis perennans (Walt.) Tuckerman

autumn bentgrass

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New England Distribution

Adapted from BONAP data

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North America Distribution

Adapted from BONAP data

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Facts About

Autumn bentgrass is a common native bunchgrass, and flowers in the latter part of the growing season. Its basal leaves usually wither by the time of flowering. The Klamath Indians of Oregon harvested the seeds for food.

Habitat

Anthropogenic (man-made or disturbed habitats), forests, shores of rivers or lakes

Characteristics

Habitat
terrestrial
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont
Leaf blade width
2–5 mm
Inflorescence branches
the flowers are attached to branches rather than to the main axis of the inflorescence
Spikelet length
1.8–2.8 mm
Glume relative length
both glumes are as long or longer than all of the florets
Awn on glume
the glume has no awn
One or more florets
there is one floret per spikelet
Lemma awn length
0 mm
Leaf sheath hair type
there are no hairs on the surface of the leaf sheath
Leaf ligule length
0.7–7.3 mm
Anther length
0.4–0.9 mm
Show All Characteristics
  • Flowers
    Anther length
    0.4–0.9 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
    1
    Floret types within spikelet
    all the florets within a spikelet are similar
    Glume awn length
    0 mm
    Glume keel
    the glume keels are rough or hairy
    Glume relative length
    both glumes are as long or longer than all of the florets
    Glume shape
    the glume is V-shaped in cross-section
    Glume veins
    1
    Glumes per spikelet
    2
    Inflorescence arrangement
    the spikelets are uniform
    Inflorescence axis orientation
    the inflorescence axis is straight
    Inflorescence branch length
    3–7 cm
    Inflorescence branch roughness
    the inflorescence branches are smooth or only slightly rough
    Inflorescence branches
    the flowers are attached to branches rather than to the main axis of the inflorescence
    Inflorescence branches coming off the lowest stem node
    1–13
    Inflorescence crowding
    the panicle is somewhat to very spread out, with clearly-evident branches
    Inflorescence length
    100–250 mm
    Inflorescence length to width ratio
    2.3–4
    Inflorescence type (general)
    the spikelets are borne on stalks or on branches
    Inflorescence type (specific)
    the inflorescence is branched, and the branches do NOT both grow from the same side of the plant AND look like spikes
    Inflorescence width
    25–110 mm
    Inforescence position
    the spikelets are mainly carried at the end of the stem
    Lemma awn base
    NA
    Lemma awn coiled
    NA
    Lemma awn length
    0 mm
    Lemma awn number
    the lemma has no awn
    Lemma awn orientation
    NA
    Lemma base hair length
    Up to 0.3 mm
    Lemma base hairs
    the lemma has hairs at the base
    Lemma cross-section
    the lemma is flat or rounded if you cut across the midpoint
    Lemma hairs
    the lemma is hairless between the veins
    Lemma keel hairs
    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 has a ragged edge
    • the lemma tip is split into two or more points
    Lemma tip shape
    • the lemma tip is rounded off or truncate (ends abruptly in a more or less straight line as though cut off); it may or may not also have an awn or teeth at the tip
    • the lemma tip tapers to a broad 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
    Up to 3.2 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 one floret per spikelet
    Palea length
    0–0.1 mm
    Palea relative length
    palea is less than one half as long as lemma or absent
    Reproductive system
    all the flowers on the plant have both carpels and stamens (synoecious)
    Spikelet axis length
    0 mm
    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
    1.8–2.8 mm
    Spikelet number per node
    0
    Spikelet pedicel
    the spikelets have pedicels
    Spikelet pedicel length
    1–7.3 mm
    Spikelet position
    the spikelets emerge mainly from the upper halves of the inflorescence branches
    Spikelet shape
    • the spikelets are lanceolate (lance-shaped, widest below the middle and tapering narrowly to the ends) in profile
    • the spikelets are ovate (egg-shaped, widest below the middle with rounded ends) in profile
    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
    At least 1.8 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
    Seed length
    1.1–1.9 mm
  • 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 do not have auricles
    Leaf basal lobe hairy
    NA
    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
    Leaf blade length
    6–20 cm
    Leaf blade texture
    the leaf blade is rough and sandpapery
    Leaf blade width
    2–5 mm
    Leaf ligule length
    0.7–7.3 mm
    Leaf ligule type
    • the leaf ligule is in the form of a membrane
    • the leaf ligule is in the form of a membrane with fine hairs
    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 no hairs on the surface of the leaf sheath
    Leaf sheath hairs
    there are no hairs on the surface of the leaf sheath
  • Place
    Habitat
    terrestrial
    New England state
    • Connecticut
    • Maine
    • Massachusetts
    • New Hampshire
    • Rhode Island
    • Vermont
    Specific habitat
    • forests
    • man-made or disturbed habitats
    • shores of rivers or lakes
  • Stem, shoot, branch
    Hairs at nodes
    the stem nodes are hairless or they have very sparse hairs
    Plant height
    20–80 cm
    Roots at lower stem nodes
    • no
    • yes
    Stem hairs
    the stem is nearly to completely hairless
    Stem node number
    3–10
    Stem orientation
    the stems are upright
    Stem spacing
    the stems grow close together in compact clusters or tufts

Wetland Status

Usually occurs in non-wetlands, but occasionally in wetlands. (Wetland indicator code: FACU)

New England Distribution and Conservation Status

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.

Massachusetts
unranked (S-rank: SNR)

Native to North America?

Yes

Synonyms

  • Agrostis altissima (Walt.) Tuckerman
  • Agrostis perennans var. elata (Pursh) A.S. Hitchc.
  • Cornucopiae perennans Walt.

Family

Poaceae

Genus

Agrostis

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