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- Poaceae Group 4
- Briza
- Briza media
Briza media — perennial quaking grass
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Facts
Perennial quaking grass is a Eurasian grass that has become relatively common in parts of northeastern North America where it has been introduced. It gets its common name from the attractive spikelets that hang from a threadlike rachis and sway or "quake" in the slightest breeze. It is sometimes cultivated.
Habitat
Anthropogenic (man-made or disturbed habitats), fens, meadows and fields
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
- 1.9–3.2 mm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Spikelet length
- 4–5.5 mm
- Glume relative length
- neither glume is quite as long as all of the florets
- Awn on glume
- the glume has no awn
- One or more florets
- there is more than one floret per spikelet
- Lemma awn length
- 0 mm
- Leaf ligule length
- 0.5–1 mm
- Anther length
- 1.3–2 mm
-
Flowers
- Anther length
- 1.3–2 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
- 3–10
- Floret types within spikelet
- all the florets within a spikelet are similar
- Glume awn length
- 0 mm
- Glume keel
- NA
- Glume relative length
- neither glume is quite as long as all of the florets
- Glume shape
- the glume is flat or curved in cross-section
- Glume veins
-
- 3
- 5
- 7 or more
- Glumes per spikelet
- 2
- Inflorescence arrangement
- the spikelets are uniform
- Inflorescence axis orientation
- the inflorescence axis is straight
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Inflorescence crowding
- the panicle is somewhat to very spread out, with clearly-evident branches
- Inflorescence length
- 80–200 mm
- 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
- Up to 200 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
- 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 flat or rounded if you cut across the midpoint
- Lemma hairs
- the lemma is hairless between the veins
- Lemma keel hairs
- NA
- 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)
- Lemma vein number
- 7 or more
- Lemma vein orientation
- the veins on the lemma come together near the tip
- Lower glume length
- 2.5–3.2 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 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 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
- 4–5.5 mm
- Spikelet number per node
- Up to 0
- Spikelet pedicel
- the spikelets have pedicels
- Spikelet pedicel length
- 5–20 mm
- Spikelet shape
- the spikelets are ovate (egg-shaped, widest below the middle with rounded ends) in profile
- Spikelet width
- 4–7 mm
- 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
- 2.5–4 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
- Seed length
- 1.2–1.5 mm
-
Growth form
- Horizontal rooting stem
- no
- 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
- 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
- 4–16 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
- 1.9–3.2 mm
- Leaf ligule length
- 0.5–1 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 color and persistence
- the leaf sheathes are off-white to light-brown and mostly persist in older leaves
- 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
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Vermont
- Specific habitat
-
- fens
- man-made or disturbed habitats
- meadows or fields
-
Stem, shoot, branch
- Hairs at nodes
- the stem nodes are hairless or they have very sparse hairs
- Plant height
- 15–75 cm
- 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.
- Massachusetts
- not applicable (S-rank: SNA)
From Flora Novae Angliae dichotomous key
1. Briza media L. E
perennial quaking grass. CT, MA, ME, NH, VT. Roadsides, fields, disturbed soil. This species was reported from RI by Kartesz (1999), based on George (1992); however, George (1999) stated this species had questionable naturalization and reported no occurrences (i.e., the author is unaware of any collections).
Native to North America?
No
Sometimes confused with
- Briza minor:
- ligules 4-13 mm long, pointed at the apex, and anthers 0.4-0.5 mm long (vs. B. media, with ligules 0.5-1 mm long, truncate at the apex, and anthers 1.3-2 mm long).
- Bromus briziformis:
- leaf sheaths with margins fused together for most of their length forming a closed tube, lemmas 9-10 mm long, and anthers 0.7-1 mm long (Vs. B. media, with leaf sheaths with margins distinct and overlapping for most of their length, lemmas 3-4 mm long or shorter, and anthers 1.3-2 mm long).