Flora of North America species comparison

10-70 cm, decumbent, branching and rooting at the lower nodes.

5-200 cm, erect or decumbent, usually geniculate;

nodes and internodes usually glabrous.

compressed, glabrous or pubescent;

ligules 1-2.1 mm;

blades 2-14 cm long, 3-14.2 mm wide.

open, usually glabrous;

ligules membranous, ciliate, cilia as long as or longer than the basal membrane;

blades flat or folded, margins cartilaginous, scabridu-lous.

2-8.2 cm;

fascicles 9-16 mm long, 4-8 mm wide, imbricate, ovoid, densely pubescent;

bristles 15-43;

outer bristles usually present, flattened or terete;

inner bristles 4-8 mm long, 1.2-3 mm wide, fused for at least 1/2 their length, forming a distinct cupule, the distal portions diverging at irregular intervals from the cupule, stramineous or purple.

terminal, spikelike panicles of highly reduced branches termed fascicles ("burs");

fascicles consisting of 1-2 series of many, stiff, partially fused, usually retrorsely scabridulous to strigose, sharp bristles surrounding, sometimes almost concealing, 1-4 spikelets;

outer (lower) bristles, if present, in 1 or more whorls, terete or flattened;

inner (upper) bristles usually strongly flattened, fused at least at the base and forming a disk, frequently to more than 1/2 their length and forming a cupule;

disarticulation at the base of the fascicles.

1(2) per fascicle, 6-8.8 mm.

sessile, with 2 florets;

lower florets usually sterile;

upper florets bisexual.

1-4 mm;

upper glumes 4.9-6.8 mm, 3-7-veined;

lower lemmas 5.5-7.5 mm, 3-7-veined, enclosing the palea;

upper lemmas 6-8.7 mm;

anthers 0.8-2.8 mm.

ovate, scarious, glabrous, 1-veined, acute to acuminate;

upper glumes and lower lemmas ovate, 3-9-veined;

lower paleas equaling the lemmas, tawny or purplish;

upper lemmas and paleas subequal, indurate, ovate, obscurely veined, acuminate.

2.6-4 mm long, 2.2-3.1 mm wide, ovoid-elliptic.

obtrulloid.

= 17.

= 34.