blue grama

not listed

N3N5 - Vulnerable to Secure

SNR - Unranked

not listed

Blue grama is a relatively short, erect or ascending, long-lived, perennial grass that rises from fibrous roots and often a short, stout rhizome. It forms dense tufts or, under heavy grazing, sod. It is an important forage species and is prominent on the short-grass prairies of the Great Plains.

The culms are erect or ascending. They can be 6″ to 24″ tall but are usually no more than 12″ in height. They are unbranched, have usually 2 or 3 nodes, and are not woody at the base. They are hairless between the lower nodes.

The leaves are mostly basal, ¾″ to 6″ long, 1 ⁄32″ to 1 ⁄16″ wide, and usually somewhat curled. They are flat or have margins that are rolled inward toward the upper side, especially toward the tip. The upper surface has short, soft hairs, especially near the base, or is rough to the touch with short, stiff hairs. The lower surface is smooth or lightly rough to the touch. The margins have short hairs near the base.

The leaf sheaths are open, rounded on the back, and mostly hairless. The lowermost sheath is sometimes sparsely covered on the inside with soft, straight hairs. The ligule is a dense fringe of short hairs. The collar is distinctly yellowish-green. There are no ear-like appendages (auricles) at the base of the blade.

The inflorescence is 1 to 6, usually no more than 4, loosely spaced spikes at the end of the stem. The spikes are 9 ⁄16″ to 19 ⁄16″ long and are straight at first, curling upward at maturity to resemble human eyelashes. Each spike has 20 to 60 densely packed spikelets arranged in 2 rows along one side of the central axis (rachis). The rachis does not extend past the uppermost spikelet.

The spikelets are about 3 ⁄16″ long. The anthers are yellow. The upper glume is sparsely hairy along the midvein.

The fruit is grain about ⅛″ long.

6″ to 12″

Hairy grama (Bouteloua hirsuta var. hirsuta) spike rachis extends ⅛″ to ⅜″ beyond the uppermost spikelet forming a stiff bristle. The upper glume is densely hairy along the midvein.

Dry. Prairies.

July to September

Sources

2, 3, 4, 5, 7, 28, 29, 30.

Native

Common

Plant

Inflorescence