Flower:

Branching cluster at the top of the stem, 6 to 30 inches long, lance-linear in outline, the branches up to 9 inches long and erect to ascending to spreading, with branchlets mostly arranged on the upper half to 2/3 of the branch. Spikelets (flower clusters) are overlapping at the tip of a branchlet but not tightly crowded, and are short-stalked, narrowly lance-elliptic in outline with a single floret.

At the base of a spikelet is a pair of bracts (glumes) that are thin, papery, narrowly egg-shaped with a pointed tip, initially whitish with a green keel drying whitish to pale brown, the upper glume 5 to 8.2 mm long, the lower glume about ¾ as long. Florets are surrounded by a pair of bracts (lemma and palea), the lemma thin and papery, 3.5 to 7 mm long, awnless, 1-veined, the palea more or less as long. The thickened base of the floret (callus) is densely covered in long, white hairs that are at least half as long as the floret but are all or mostly hidden by the glumes.

Leaves and stems:

Leaves are 12 to 24 inches long, 5 to 12 mm (to ~½ inch) wide, gray-green to blue-green, hairless, mostly floppy, flat towards the base and rolled inward along the edges (involute) above, and gradually tapering to a thread-like tip. Five to 10 leaves are alternately attached along the stem, the lower leaves more crowded than the upper with sheaths overlapping.

The sheath is usually hairy along the edge at the tip, with short and/or long white hairs; the surface is hairless or sparsely to densely hairy. The ligule (membrane where the leaf joins the sheath) is a fringe of hairs up to 1 mm long. Nodes are smooth, not much swollen, and often hidden by the sheaths. Stems are hairless, unbranched, mostly erect, usually single, sometimes forming loose clumps. Plants form colonies from long, scaly rhizomes.

Fruit:

Spikelets are whitish to pale brown at maturity, the florets shedding individually as each grain matures, leaving the glumes behind. Grains (seeds) are light brown, 2.5 to 4.5 mm long.

Notes:

Sand Reed Grass is a fairly common grass of dry, sandy soils. There are 2 recognized varieties: var. magna with spreading to ascending panicle branches, spikelets overlapping no more than 1 other spikelet, and usually hairy sheaths, is present from Wisconsin to New York, mostly around the Great Lakes; var. longifolia, present from Wisconsin westward, has erect to ascending panicle branches, spikelets overlapping 2 or 3 other spikelets, and usually hairless sheaths except at the tip along the edges. The species in Minnesota, var. longifolia, is distinguished from other grasses with a similar panicle by the single-flowered spikelets, the long hairs around the base of the floret (usually hidden by the glumes), the fringe of hairs for a ligule, and the long floppy leaves becoming thread-like at the tip. Usually a fairly tall grass, the colonies of pale, slender panicles with somewhat silvery foliage tend to stand out.