Panicum bergii |
Panicum mohavense |
|
---|---|---|
Berg's panicgrass, Bergs witchgrass |
Mohave witchgrass, Mojave panicgrass |
|
Habit | Plants perennial; cespitose, with numerous leaves clustered at the base. | Plants annual. |
Culms | (10)50-140 cm, stout, stiffly erect, branched from the middle and lower nodes; lower nodes sericeous; lower internodes sericeous, hairs papillose-based, upper internodes sometimes glabrous. |
2-8 cm, erect-spreading; nodes 1-2, hispid; internodes pilose, hairs papillose-based. |
Sheaths | rounded, glabrous or sparsely to densely hispid, hairs not fragile and prickly, not causing skin irritation, margins ciliate; ligules 1-3 mm; blades 3-60 cm long, 2-12 mm wide, flat or involute, ascending, adaxial surfaces densely hirsute basally, less densely so elsewhere, bases attenuate, apices acute. |
rounded, much longer than the internodes, with prominent veins, hispid, hairs papillose-based; ligules 0.2-0.4 mm, membranous, ciliate; blades 1-4 cm long, 1-3 mm wide, flat or involute apically, glabrous basally, margins ciliate, cilia papillose-based. |
Panicles | (4)15-40 cm long, (3)10-25 cm wide, about 1/3 – 1/2 as long as the plants, open, breaking at the base of the peduncles at maturity and dispersed as tumbleweeds, secondary branching mostly confined to the distal 1/3 of the primary branches; rachises densely hispid or glabrous; lower primary branches in whorls of 4-7, stiffly spreading, naked on the lower 1/2; pedicels 3-20 mm, appressed. |
congested, partially included in the sheaths, less than 1.5 times longer than wide; branches ascending, narrow; primary branches appressed to the main axes, secondary branches and pedicels attached to the distal 2/3; pedicels appressed, 1-2 mm. |
Spikelets | 2-3 mm long, 0.8-1.2 mm wide, glabrous. |
2-2.2 mm long, 1-1.3 mm wide, plump-ellipsoid, glabrous. |
Lower glumes | 1-1.6 mm, 5-veined, acuminate; upper glumes and lower lemmas similar, 2-2.8 mm, 7-9-veined, exceeding the upper florets by about 0.3 mm; lower florets sterile; lower paleas 1.4-2.2 mm; upper florets 1.5-1.9 mm long, 0.7-1 mm wide, smooth, chestnut brown at maturity. |
1.2-1.3 mm, acute to attenuate; upper glumes and lower lemmas 2-2.2 mm, 7-9-veined, apices purplish, acute; lower florets sterile; lower paleas 0.2-0.4 mm; upper florets 1.4-1.8 mm long, about 1 mm wide, broadly ovoid. |
2n | = 36. |
|
Panicum bergii |
Panicum mohavense |
|
Distribution |
AL; GA; LA; TX |
AZ; NM |
Discussion | Panicum bergii is an eastern South American species that now grows in southeastern Texas. It occurs in ditches and shallow, and sporadically flooded depressions in grasslands. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Panicum mohavense is known only from arid limestone terraces in Arizona and New Mexico. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 25, p. 464. | FNA vol. 25, p. 462. |
Parent taxa | Poaceae > subfam. Panicoideae > tribe Paniceae > Panicum > subg. Panicum > sect. Panicum | Poaceae > subfam. Panicoideae > tribe Paniceae > Panicum > subg. Panicum > sect. Panicum |
Sibling taxa | ||
Synonyms | P. pilocomayense | |
Name authority | Arechav. | Reeder |
Web links |