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- Poaceae Group 4
- Bromus
- Bromus rigidus
Bromus rigidus — ripgut brome
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Facts
Ripgut brome is an annual brome native to Europe, northern Africa and western Asia, and very widely introduced elsewhere in the world, including in North America. It is considered a serious weed of crops in some areas. Within New England it has been collected only near seaports in Massachusetts. The common name refers to the poor quality of this species as livestock fodder.
Habitat
Anthropogenic (man-made or disturbed habitats), 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.
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Characteristics
- Habitat
- terrestrial
- New England state
- Massachusetts
- Leaf blade width
- 3–7 mm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Spikelet length
- 25–100 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
- 30–50 mm
- Leaf sheath hair type
- there are hairs on the surface of the leaf sheath, but the hairs do not have blisters at their bases
- Leaf ligule length
- 2–5.5 mm
- Anther length
- 0.5–1 mm
-
Flowers
- Anther length
- 0.5–1 mm
- Anther number
- 2–3
- Awn on glume
- the glume has no awn
- Bristles below spikelets
- no
- Floret lower bract texture
- the lemma is thin and flexible
- Floret number
- 4–11
- Floret types within spikelet
- all the florets within a spikelet are similar
- Glume awn length
- 0 mm
- Glume relative length
- neither glume is quite as long as all of the florets
- Glume veins
- 7 or more
- Glumes per spikelet
- 2
- Inflorescence arrangement
- the spikelets are uniform
- Inflorescence axis orientation
-
- the inflorescence axis is arched or curved outward
- the inflorescence axis is straight
- Inflorescence branch length
- 1–7 cm
- 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
- Inflorescence crowding
- the panicle is somewhat to very spread out, with clearly-evident branches
- Inflorescence length
- 20–70 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 150 mm
- Inforescence position
- the spikelets are mainly carried at the end of the stem
- Lemma awn base
-
- the awn is attached at the upper half of the lemma
- 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
- 30–50 mm
- Lemma awn number
- the lemma has one awn on it
- Lemma awn orientation
- the awn of the lemma is straight
- 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 has fine hairs between the veins
- the lemma is hairless between the veins
- Lemma keel hairs
- NA
- Lemma marginal vein hairs
-
- the marginal vein of the lemma has fine hairs on it
- 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 split into two or more points
- Lemma tip shape
- the lemma tip tapers to a long narrow 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
- 13–25 mm
- 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 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
- 25–100 mm
- Spikelet number per node
- Up to 0
- Spikelet pedicel
- the spikelets have pedicels
- Spikelet shape
- the spikelets are obtriangular (triangular, with the widest end away from the point of attachment) in profile
- Spikelets per panicle branch
- 1–2
- 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
- 20–35 mm
- Upper glume shape
- 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
- Seed length
- 11–12 mm
-
Growth form
- Lifespan
- the plant lives only a single year or less
- 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 hairy
- Leaf blade length
- 10–25 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
- 3–7 mm
- Leaf ligule length
- 2–5.5 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 fused together and form a closed tube except (possibly) at the very top
- Leaf sheath hair type
- there are hairs on the surface of the leaf sheath, but the hairs do not have blisters at their bases
- Leaf sheath hairs
- there are hairs on the surface of the leaf sheath
-
Place
- Habitat
- terrestrial
- New England state
- Massachusetts
- Specific habitat
-
- 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
- the stem nodes have hairs that stand out at a shallow angle, or they curve downwards
- Plant height
- 20–100 cm
- Stem hairs
-
- the stem has hairs on it
- the stem is nearly to completely hairless
- Stem orientation
- the stems are upright
Wetland status
Not classified
In New England
Distribution
- Connecticut
- absent
- Maine
- absent
- Massachusetts
- present
- New Hampshire
- absent
- Rhode Island
- absent
- Vermont
- absent
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
15. Bromus rigidus Roth E
ripgut brome. Anisantha rigida (Roth) Hyl.; Bromus diandrus Roth ssp. rigidus (Roth) Lainz • MA. Fields, roadsides, waste areas around seaports. This species is closely related to, and sometimes included in, Bromus diandrus.
Native to North America?
No
Sometimes confused with
- Bromus rubens:
- lemmas 10-15 mm long, with awns mostly 10-20 mm long arising between two apical lobes 1-3 mm long (vs. B. rigidus, with lemmas 22-28 mm long, with awns 30-50 mm long arising between two apical lobes 3-5 mm long).
Synonyms
- Anisantha rigida (Roth) Hyl.
- Bromus diandrus Roth ssp. rigidus (Roth) Lainz