Bromus arizonicus
Bromus scoparius
Arizona brome
broom brome
30-90 cm tall, to 3 mm thick, erect.
(9)20-40 cm, erect or ascending.
retrorsely pilose, sometimes mostly glabrous, throats sometimes with hairs;
auricles absent;
ligules 1-4 mm, usually glabrous, obtuse, erose;
blades 8-18 cm long, 3-9 mm wide, flat, sparsely pilose on both surfaces or the abaxial surfaces glabrous.
sparsely pubescent or glabrous;
ligules 0.8-1.5 mm, glabrous or hairy, obtuse;
blades 5-20 cm long, 2-5 mm wide, abaxial surfaces glabrous, adaxial surfaces pilose.
12-25 cm, somewhat contracted or open;
lower branches shorter than 10 cm, 2-3(5) per node, initially erect to ascending, spreading at maturity, with 1-2 spikelets variously distributed.
2-7 cm long, 1-4 cm wide, erect, dense, obovoid, wedge-shaped at the base, sometimes interrupted;
branches shorter than the spikelets, erect, straight or almost so, sometimes verticillate.
18-25 mm, elliptic to lanceolate, strongly laterally compressed, with 4-8 florets.
12-25 mm, lanceolate, crowded, terete to moderately laterally compressed;
florets 5-10, bases concealed at maturity;
rachilla internodes concealed at maturity.
subequal, smooth or scabrous;
lower glumes 8-12.5 mm, 3-veined;
upper glumes 9.5-14 mm, 7-veined, about as long as the lowest lemma;
lemmas 9.5-14 mm, lanceolate, laterally compressed, prominently 7-veined, strongly keeled at least distally, glabrous or pubescent distally or throughout, marginal hairs, if present, longer than those elsewhere, apices entire or with acute teeth shorter than 1 mm;
awns 6-13 mm, sometimes slightly geniculate;
anthers 0.4-0.5 mm.
scabrous to pubescent;
lower glumes 3-4 mm, 3-5-veined;
upper glumes 5-7 mm, 5-7-veined;
lemmas 7-10 mm long, 1.5-2 mm wide, lanceolate, glabrous, obscurely 7-veined, rounded over the midvein, margins rounded, not inrolled at maturity, apices sharply acute, bifid, teeth shorter than 1 mm;
awns 7-10 mm, flattened at the base, divaricate or recurved when mature, arising 1.5 mm or more below the lemma apices;
anthers 0.3-0.5 mm.
shorter than the paleas, thin, weakly inrolled or flat.
= 84.
= 14.
Bromus arizonicus
Bromus scoparius
Bromus arizonicus grows in dry, open areas and disturbed ground of the southwest, usually below 2000 m. Its range extends from California and southern Nevada into Arizona, New Mexico, and northern Mexico.
Stebbins et al. (1944) demonstrated that, like Bromus carinatus var. carinatus, B. arizonicus obtained three of its genomes from B. catharticus or a close relative, but the remaining three genomes are not homologous with those in B. carinatus, probably being derived from a species in a section other than Ceratochloa. The small anthers of B. arizonicus strongly suggest that most seed is produced by selfing.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Bromus scoparius is native to southern Europe. It grows in waste places. In the Flora region, it has been recorded from Californica and New York.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
CA
WildflowerSearch
iNaturalist
USDA Plants Database
MI Flora
