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• Thinopyrum pycnanthum

Thinopyrum pycnanthum — tick quack grass

Facts

Tick quack grass is a non-native grass that has colonized salt marshes and beaches on parts of the Atlantic and Pacific coasts. It is found in Massachusetts, Maine and Rhode Island.

Habitat

Coastal beaches (sea beaches), marshes

Characteristics

• Flowers

  Anther length

  5–7 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

  3–10

  Floret types within spikelet

  all the florets within a spikelet are similar

  Glume awn length

  0–0.7 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

  • 5
  • 7 or more

  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

  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

  40–200 mm

  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)

  Inforescence position

  the spikelets are mainly carried at the end of the stem

  Lemma awn length

  0–10 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 hairs

  the lemma is hairless between the veins

  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 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

  4.5–8 mm

  Lower glume relative length

  • the lower glume is nearly as long, or as long as, the upper glume
  • the lower glume is one third to three quarters as long as the upper glume

  One or more florets

  there is more than one floret per spikelet

  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

  10–20 mm

  Spikelet pedicel

  the spikelets do not have pedicels

  Spikelet pedicel length

  0 mm

  Spikelet position

  NA

  Spikelets per panicle branch

  0

  Spikelets spiny

  the spikelets appear spiny and bur-like

  Tip of glume

  the tip of the glume is not divided (though it may have an awn on it)

  Upper glume length

  4.5–8 mm

  Upper glume shape

  • the upper glume is widest above the middle
  • the upper glume is widest at or below the middle

• Growth form

  Lifespan

  the plant lives more than two years

  Rhizomes

  yes

  Roots

  the plant has rhizomes (horizontal underground stem with roots growing from it)

• Leaves

  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

  Leaf blade length

  Up to 35 cm

  Leaf blade texture

  the leaf blade is rough and sandpapery

  Leaf blade width

  2–6 mm

  Leaf ligule length

  0.3–0.6 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 hairs

  there are no hairs on the surface of the leaf sheath

• Place

  Habitat

  • terrestrial
  • wetlands

  New England state

  • Maine
  • Massachusetts
  • Rhode Island

  Specific habitat

  • marshes
  • sea beaches

• Stem, shoot, branch

  Hairs at nodes

  the stem nodes are hairless or they have very sparse hairs

  Plant height

  10–120 cm

  Stem hairs

  the stem is nearly to completely hairless

  Stem spacing

  the stems grow singly or a few together (they may form diffuse colonies)

Wetland status

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

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae