| Jesús Valdés-Reyna |
Plants annual; stoloniferous, mat-forming;
stolons 2-8 cm, terminating in fascicles of leaves from which new culms
arise. Culms 3-15(30) cm. Leaves mostly basal, sometimes with a
purple tint; sheaths with a tuft of hairs at the throat; auricles
absent; ligules of hairs; blades linear, usually involute, sometimes
flat or folded, with white, thickened margins, apices sharply pointed. Inflorescences
terminal, capitate panicles of spikelike branches; branches almost completely
hidden in a subtending leafy bract, with 2-4 subsessile or pedicellate spikelets.
Spikelets laterally compressed, with 2-10 florets; lower florets
bisexual or pistillate; terminal florets sterile; disarticulation
above the glumes or beneath the leaves subtending the branches. Glumes
shorter than the spikelets, keeled, 1-veined, unawned; lower glumes usually
present on all spikelets (absent from all spikelets in M. mendocina); upper
glumes absent or reduced on the terminal spikelet; lemmas with a pilose
tuft of hairs along the margins at midlength, membranous or coriaceous, 3-veined,
lateral veins occasionally shortly excurrent, apices emarginate or 2-lobed; paleas
glabrous, smooth; lodicules present or absent, truncate; anthers
2 or 3, yellow; style branches elongate, 2(3), barbellate. Caryopses
dorsally compressed. x = 7 or 8. Named for Sir William Munro (1818-1880),
a British botanist who collected in Barbados, the Crimea, and India.
Munroa, a genus of five species, is endemic to the Western Hemisphere.
One species occurs in the Flora region, the remainder being confined to
South America. Its closest relatives are thought to be Blepharidachne and Dasyochloa, both of which are stoloniferous,
mat-forming species with leafy-bracteate panicles. Munroa differs from
both in its annual habit.
1. Munroa squarrosa (Nutt.) Torr.
False Buffalograss
Stolons slender. Culms 3-15(30) cm, highly branched, scabrous, often
minutely puberulent. Ligules 0.5(1) mm; blades 1-5 cm long, 1-2.5
mm wide. Spikelets 6-8(10) mm, with 3-5 florets. Glumes of first 1-2
spikelets subequal, 2.5-4.2 mm, narrow, 1-veined, acute; glumes of upper
spikelets unequal, lower glumes reduced or even absent in the terminal spikelets;
lemmas in lower spikelets scabridulous, lanceolate, midvein excurrent,
forming a stout, scabrous 0.5-2 mm awn, lateral veins with a tuft of hairs on
the margins near midlength, excurrent; anthers 1-1.5 mm. 2n = 16.
Munroa squarrosa grows in dry, open areas, usually in sandy soil or disturbed
sites, from Saskatchewan and Alberta south to Chihuahua, Mexico.