Narrow-flowered Brome

Bromus vulgaris
Species distinguishing characteristics: 
  • Perennial bunchgrass forms loose tufts from fibrous roots
  • Stems are hairy at the nodes 
  • Long, flat, lax leaf blades with jagged ligules
  • Leaf sheaths closed with a few long hairs at throat
  • Green, nodding, open flower clusters with cylindrical, slightly compressed spikelets
  • Lemmas hairy on the margins and rounded on the backs
  • Awns are 5–10 mm long
Family Characteristics: 
  • Flowering stems have nodes and are hollow and round in cross section
  • Alternate leaves sheath the stem on the lower portion, and form a hairy or membranous scale (ligule) inside the base of the leaf sheath
  • Flower clusters of numerous spikelets attach directly to the flowering stem (spike) or attach by small stalks and are often branched (panicle)
  • A pair of bracts, called glumes, enclose spikelets at the base (the outer/lower glume being larger)
  • Each spikelet has one or more florets (dry, single seed flowers) surrounded by 2 bracts (a lower lemma and a smaller upper palea)
  • Lemmas and/or glumes may have needle-like, stiff hairs (awns)
  • Florets have 3 stamens (pollen organs) and 2 feathery stigmas (tip of female organ for receiving pollen), but lack showy petals and sepals as they are wind pollinated
  • Fruit is a seed-like grain enclosed in bracts (called chaff in cereal grains)
  • Well known members of this family include cereal grains such as wheat (Triticum), rice (Oryza), corn (Zea), and oats (Avena)
Growth habitat: 

Perennial bunchgrass, 45–120 cm tall, forms loose tufts from fibrous roots.

Leaves and stems: 

Slender, erect stems are usually hairy at the nodes.  Flat leaf blades, 5–10 mm wide and 12–30 cm long, are lax and usually short haired on at least one surface (usually the upper surface).  The smooth to soft haired leaf sheaths fuse around the stem for most of their length but have a few long hairs at the opening near the ligules.  The ligules, 2–6 mm long, are fine to coarsely jagged.  Lacks auricles, or small, clasping appendages on the collar of the leaf sheath.

Flowers: 

Flower cluster is a pale green, diffuse panicle, 8–22 cm long, with slender, drooping (or occasionally spreading) branches.  The slender, elongated spikelets, 1.5­–3 cm long with 5–7 florets, are cylindrical but slightly compressed and typically all droop in the same direction.  The glumes are keeled on their backs.  The lower glume, 5–8 mm long, usually has 1 nerve, and the upper glume, 7–10 mm long, has 3 nerves.  The lemmas, 8–16 mm long, are hairy along the margins but smooth toward the tip and rounded on their backs.  Awns, 5–10 mm long, emerge from 2 shallow teeth at the tip of the lemmas.  The yellow pollen sacs protrude out of the florets during blooming.

Roots: 

Fibrous, loosely clumped roots.  Non-rhizomatous, but it may sometimes spread vegetatively by rooting at the lower nodes along the stems.

Habitat preferences: 

Dry to moist, nitrogen-rich soils of open forests (mostly coniferous but also broad-leaved), meadows, thickets, rocky slopes, stream banks, and gravel river bars at low to subalpine elevations.  Tolerates and may thrive in partial shade.

Interesting facts: 

Also called columbia brome.  Narrow-flowered brome provides valuable forage for elk (Cervus elaphus), deer (Cervidae spp.), and livestock before flowering and may increase its growth in response to moderate grazing.  Bromus is an ancient word referring to oats.  Tribal groups ate the seeds of many Bromus species.

This species is often added to seed mixes for use as pasture grass and in projects aimed at enhancing wildlife forage.  It is commonly used for re-vegetation via direct seeding after disturbance.  The ability to root from the lower nodes of stems allows narrow-flowered brome to re-sprout after grass fires that burn only the tops of vegetation.

Biological Classification: