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• Lolium multiflorum

Lolium multiflorum — Italian rye grass

Facts

Italian rye grass, a European species, is a very widespread non-native grass found in fields, roadsides and disturbed areas across much of the temperate world. It has been widely planted as a cover crop, forage, and lawns. It can interbreed with its close relative, Lolium perenne (perennial rye-grass). It is distinguished from this species by the comparatively long awns on the spikelets, the rough texture of the inflorescence axis (rachis), and the wider leaves that are rolled (not folded) when still in bud.

Habitat

Anthropogenic (man-made or disturbed habitats), meadows and fields

Characteristics

• Flowers

  Anther length

  2.5–5 mm

  Anther number

  3

  Awn on glume

  the glume has no awn

  Bristles below spikelets

  no

  Floret lower bract texture

  • the lemma is hard and firm
  • the lemma is thin and flexible

  Floret number

  10–22

  Floret types within spikelet

  all the florets within a spikelet are similar

  Glume awn length

  0 mm

  Glume keel

  the glume keels are smooth and hairless

  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

  • 1
  • 2

  Inflorescence arrangement

  the spikelets are uniform

  Inflorescence axis hairs

  the inflorescence axis is rough and feels like sand-paper

  Inflorescence axis orientation

  • the inflorescence axis is arched or curved outward
  • 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

  150–450 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 base

  the awn is attached at the upper half of the lemma

  Lemma awn coiled

  the lemma awn is straight or twisted, but not coiled one half turn

  Lemma awn length

  0–10 mm

  Lemma awn number

  • the lemma has no awn
  • 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 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 vein number

  • 5
  • 7 or more

  Lemma vein orientation

  the veins on the lemma stay roughly parallel throughout

  Lower glume length

  0–18 mm

  One or more florets

  there is more than one floret per spikelet

  Palea relative length

  • palea is longer than lemma
  • 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

  8–31 mm

  Spikelet number per node

  Up to 1

  Spikelet pedicel

  the spikelets do not have pedicels

  Spikelet pedicel length

  0 mm

  Spikelet position

  NA

  Spikelet shape

  • the spikelets are elliptic (widest in the middle, tapering to the ends) in profile
  • the spikelets are oblong (rectangular, but with rounded ends) in profile
  • the spikelets are ovate (egg-shaped, widest below the middle with rounded ends) in profile

  Spikelet width

  2–10 mm

  Spikelets per panicle branch

  0

  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

  5–18 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

  2.5–4 mm

• Growth form

  Horizontal rooting stem

  no

  Lifespan

  • the plant lives more than two years
  • the plant lives only a single year or less

• Leaves

  Leaf auricles

  the leaves have auricles

  Leaf blade base

  the leaf is tapered gradually to the base

  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

  10–30 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

  2–13 mm

  Leaf ligule length

  Up to 4 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 reddish-brown and disintegrate or become shredded in older leaves

  Leaf sheath hairs

  there are no hairs on the surface of the leaf sheath

  Orientation of topmost leaf

  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

  • 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

  Up to 150 cm

  Stem hairs

  the stem is nearly to completely hairless

  Stem orientation

  • the stems are upright
  • the stems trail along the ground or on other plants through most or all of their length

  Stem spacing

  the stems grow close together in compact clusters or tufts

Wetland status

Occurs most often in non-wetlands, but rarely in wetlands. (Wetland indicator code: FACU-)

New England distribution and conservation status

From the dichotomous key of Flora Novae Angliae