4. Sporobolus cryptandrus (Torr.) A. Gray (sand dropseed)
Pl. 155
d–f; Map 626
S. cryptandrus var. fusicolor (Hook.) R.W. Pohl
Plants perennial, forming tufts. Flowering stems 25–100 cm
long. Leaf sheaths with dense tufts of long (2–4 mm) hairs at the tips of the
margins, sometimes also hairy along the rest of the margins, otherwise glabrous
or roughened, the ligule 0.3–1.0 mm long. Leaf blades 2–26 cm long, 2–6 mm
wide, flat or with inrolled margins, glabrous or somewhat roughened. Inflorescences
15–40 cm long, terminal, spikelike to more or less open panicles, mostly
enclosed by to mostly free from the subtending leaf sheath, the free portion
varying from linear to narrowly elliptic or ovate in outline, the branches
appressed or ascending to spreading, with dense spikelets nearly to the base,
the lowermost ones alternate. Spikelets 1.5–2.8 mm long, the glumes noticeably
unequal in length, the lower glume about 1/2 as long as the upper glume. Lower
glume 0.6–1.9 mm long, narrowly lanceolate, sharply pointed at the tip. Upper
glume 1.5–2.6 mm long, 3/4 to about as long as the floret, lanceolate to
narrowly elliptic‑ovate, sharply pointed at the tip. Lemma 1.4–2.8 mm
long, elliptic‑ovate, 1‑nerved, sharply pointed at the tip,
glabrous. Paleas slightly shorter than the lemmas. Anthers 0.1–1.1 mm long.
Fruits 0.6–1.2 mm long, oblong‑obovate in outline, reddish orange. 2n=18,
36, 38, 72. August–October.
Scattered, mostly in counties adjacent to the Missouri and Mississippi Rivers, uncommon elsewhere in southern Missouri (northeastern,
central, and western U.S. and adjacent Canada; Mexico). Banks of rivers,
margins of lakes, loess hill prairies, sand prairies, openings of dry upland
forests, and ledges and tops of bluffs, in sandy soils; also fallow fields, old
fields, mine spoils, railroads, roadsides, and sandy, open, disturbed areas.
This species is nearly restricted to sandy habitats, except
for a few occurrences on dolomite bluffs. Steyermark (1963) suggested that
eventually it would be found in every county bordering the large rivers. Sand
dropseed apparently was used as a food by Native Americans, who ground the
dried fruits into a flour for baking.