Flower:

Flowering head is an open panicle 4 to 8 inches long, either nodding to one side with arching branches or more erect with spreading but droopy branches, and 2 or more spikelets (flower clusters) per branch. Spikelets are stalked, oblong-elliptic in outline, only slightly flattened, 15 to 30+ mm (to 1+ inch) long, with 5 to 10 florets. One or more sterile florets may be at the tip.

At the base of a spikelet is a pair of bracts (glumes), both usually hairy, pointed at the tip, the lower glume 4 to 8 mm long and 1-veined, the upper glume 5 to 10 mm long and usually 3-veined, rarely 5-veined. Surrounding a floret is a pair of bracts (lemma and palea). Lemmas are lance-elliptic, papery, 8 to 12 mm long, 5-veined, notched at the tip forming 2 teeth, a straight awn 3 to 8 mm long arising between the teeth, and the lemma body usually evenly short-hairy on the surface, rarely hairless. The palea is somewhat shorter than the lemma, 2-veined and hairy along the veins. Sterile florets are like the fertile but underdeveloped.

Leaves and stems:

Stem leaves number 4 to 6, are spreading to ascending, flat, 5 to 12 inches long, 8 to 15 mm (to ½+ inch) wide, variously hairy, sometimes hairless on one or both surfaces.

Sheath edges are fused for most of their length (a closed sheath), usually covered in spreading or downward pointing (retrorse) hairs, rarely hairless. The ligule (membrane where the leaf joins the sheath) is membranous, .5 to 2 mm long, jagged along the top edge and lacks a fringe of hairs. Nodes are usually hairy. Stems are a few to several from the base forming clumps, mostly erect, hairless or hairy just at the nodes.

Fruit:

Florets mature to light brown, each dropping off individually leaving the glumes persisting on the stalk. Grains are somewhat flattened, elliptic, 7 to 9.5 mm long, and have a bundle of white hairs at the tip.

Notes:

Bromes are cool season grasses (optimal growth below 75°), usually clump-forming, have closed sheaths, panicles that are often drooping or nodding to one side, multi-flowered spikelets, unequal glumes, and lemmas that are typically awned, hairy and usually notched at the tip forming 2 teeth with the awn arising between the teeth. The longer leaves also frequently twist from near the base so the underside and upperside are flipped. Most Bromes found in Minnesota have sheaths and nodes that are hairy to various degrees and are mostly distinguished by the number of veins on the glumes, length of the lemma awns, and sometimes leaf characteristics.

Hairy Woodland Brome, formerly Bromus purgans, is distinguished by a 1-veined lower glume, usually 3-veined upper glume, glumes and lemmas both usually hairy, lemmas with awns 3 to 8 mm long, and usually hairy leaves, 4 to 6 per stem. Most similar are two other native species: Fringed Brome (Bromus ciliatus), which has long hairs only around the lemma edges and tends to prefer more open habitat, and Earlyleaf Brome (Bromus latiglumis), which blooms much later (August-September), has auricled sheaths, mostly hairless leaves, and much leafier stems (8 to 20 leaves) with all of the nodes covered up by the sheaths.