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• Dichotomous Key
• Poaceae
• Poaceae Group 2
• Cynosurus
• Cynosurus cristatus

Cynosurus cristatus — crested dogtail grass

Facts

Crested dogtail grass is a Eurasian perennial, widely introduced elsewhere, including eastern and western North America. It can be found in all New England states in roadsides and other disturbed sites. This species is sometimes cultivated as an ornamental grass, and it is also used in revegetation projects.

Habitat

Anthropogenic (man-made or disturbed habitats)

Characteristics

• Flowers

  Anther length

  1.8–3 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 hard and firm
  • the lemma is thin and flexible

  Floret number

  2–18

  Floret types within spikelet

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

  Glume awn length

  At least 0 mm

  Glume keel

  the glume keels are rough or hairy

  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

  1

  Glumes per spikelet

  2

  Inflorescence axis orientation

  • the inflorescence axis is arched or curved outward
  • the inflorescence axis is straight

  Inflorescence branch roughness

  the inflorescence branches are somewhat to very rough

  Inflorescence branches

  • the flowers are attached to branches rather than to the main axis of the inflorescence
  • there are no branch points between the base of the inflorescence axis and the flowers, or they are not obvious

  Inflorescence crowding

  • the panicle is somewhat to very congested (crowded), and the branches may not be clearly seen without close inspection
  • the panicle is somewhat to very spread out, with clearly-evident branches

  Inflorescence length

  10–140 mm

  Inflorescence length to width ratio

  2.5–14

  Inflorescence type (general)

  • the inflorescence is a spike, or is spike-like, lacking obvious branches
  • 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

  4–10 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

  0–3 mm

  Lemma awn number

  • the lemma has no awn
  • the lemma has one awn on it

  Lemma base hair length

  0 mm

  Lemma base hairs

  the lemma is hairless or feels just a tiny bit rough at the base

  Lemma cross-section

  • the lemma is V-shaped if you cut across the midpoint
  • the lemma is flat or rounded if you cut across the midpoint

  Lemma keel hairs

  • NA
  • the keel of the lemma is rough, or has fine hairs

  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 broad point (it may or may not also have an awn or teeth at the tip)
  • 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

  Lower glume length

  2.5–6 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 length

  3–4 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 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

  3–7 mm

  Spikelet number per node

  Up to 0

  Spikelet pedicel

  • the spikelets do not have pedicels
  • the spikelets have pedicels

  Spikelet pedicel length

  At least 0 mm

  Spikelet shape

  • the spikelets are obovate (egg-shaped but with the widest point above the middle) in profile
  • the spikelets are ovate (egg-shaped, widest below the middle with rounded ends) in profile

  Spikelets per panicle branch

  2

  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

  2.5–6 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

• Growth form

  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 large or prominent tufts of leaves at the base of the flowering stem

  Leaf auricles

  the leaves do not have auricles

  Leaf basal lobe hairy

  NA

  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

  3–19 cm

  Leaf blade texture

  • the leaf blade is rough and sandpapery
  • the leaf blade is smooth, or it may have soft hairs

  Leaf blade width

  0.5–4.3 mm

  Leaf ligule length

  0.5–2.5 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 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

  man-made or disturbed habitats

• Stem, shoot, branch

  Hairs at nodes

  the stem nodes are hairless or they have very sparse hairs

  Plant height

  5–24 cm

  Roots at lower stem nodes

  no

  Stem hairs

  the stem is nearly to completely hairless

  Stem node number

  1–3

  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

Occurs in wetlands or non-wetlands. (Wetland indicator code: FAC)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae