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• True grasses
• Bromus rigidus

Bromus rigidus — ripgut brome

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

Characteristics

• 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

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae