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- Poaceae Group 4
- Bromus
- Bromus arvensis
Bromus arvensis — field brome
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Facts
Field brome is native to Europe and western Asia and has become one of the most widespread non-native grasses in North America. It can be a very aggressive invader in some habitat types, but in New England it is most likely to be encountered on roadsides, in fields, and in disturbed areas.
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.
Found this plant? Take a photo and post a sighting.
Characteristics
- Habitat
- terrestrial
- New England state
-
- Connecticut
- Maine
- Massachusetts
- New Hampshire
- Rhode Island
- Leaf blade width
- 2–6 mm
- Inflorescence branches
- the flowers are attached to branches rather than to the main axis of the inflorescence
- Spikelet length
- 10–25 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
- 6–11 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
- 1–1.5 mm
- Anther length
- 3–5 mm
-
Flowers
- Anther length
- 3–5 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
- 4–10
- 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
-
- 3
- 5
- 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
- 7–15 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
- 150–200 mm
- Inflorescence length to width ratio
- 15–37.5
- 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
- 4–20 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
- 6–11 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 is hairless between the veins
- Lemma keel hairs
- NA
- 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 split into two or more points
- Lemma tip shape
- 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
- 7 or more
- Lemma vein orientation
- the veins on the lemma come together near the tip
- Lower glume length
- 4–6 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
- 10–25 mm
- Spikelet number per node
- Up to 0
- Spikelet pedicel
- the spikelets have pedicels
- Spikelet shape
- the spikelets are lanceolate (lance-shaped, widest below the middle and tapering narrowly to the ends) in profile
- Spikelet width
- 3–4 mm
- Spikelets per panicle branch
- 5–10
- 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
- 5–8 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
- 7–9 mm
-
Growth form
- Horizontal rooting stem
- no
- Lifespan
- the plant lives only a single year or less
- Rhizomes
- no
- Roots
- there are only slender roots on the plant
-
Leaves
- 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 hairy
- Leaf blade length
- 10–20 cm
- Leaf blade width
- 2–6 mm
- Leaf ligule length
- 1–1.5 mm
- Leaf ligule type
- 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 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
- 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
- Rhode Island
- Specific habitat
-
- man-made or disturbed habitats
- meadows or fields
-
Stem, shoot, branch
- Plant height
- 80–110 cm
- Stem hairs
- the stem is nearly to completely hairless
- Stem node number
- 2–5
- 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)
In New England
Distribution
- Connecticut
- present
- Maine
- present
- Massachusetts
- present
- New Hampshire
- present
- Rhode Island
- present
- 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
1. Bromus arvensis L. E
field brome. CT, MA, ME, NH, RI. Fields, roadsides, disturbed soil.
Native to North America?
No
Sometimes confused with
- Bromus secalinus:
- ligules 2-3 mm long, glabrous, and anthers 1-2 mm long (vs. B. arvensis, with ligules 1-1.5 mm long, pubescent, and anthers 3-5 mm long).