The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Hall panicum, Hall's panic, Hall's panicgrass, Hall's panicum, Hall's witchgrass

Mohave witchgrass, Mojave panicgrass

Habit Plants perennial; cespitose. Plants annual.
Culms

10-100 cm, 2-10 mm thick, erect, simple or sparingly branched basally;

nodes sericeous, pilose or glabrous;

internodes usually glaucous.

2-8 cm, erect-spreading;

nodes 1-2, hispid;

internodes pilose, hairs papillose-based.

Sheaths

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.

Leaves

often crowded basally;

sheaths rounded, glabrous or hirsute, hairs fragile, papillose-based, margins sometimes ciliate distally;

ligules 0.6-2 mm;

blades 4-23 cm long, 1-10 mm wide, erect to spreading, flat or sometimes involute (on sterile branches), often curling at maturity, glaucous, abaxial surfaces sometimes with prominent papillae along the midribs, bases rounded or narrowing to the sheaths, margins cartilaginous, ciliate basally, scabridulous elsewhere, apices acute.

Panicles

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

2.1-4.2 mm long, 0.8-1 mm wide, usually ovoid, glabrous.

2-2.2 mm long, 1-1.3 mm wide, plump-ellipsoid, glabrous.

Lower glumes

1.2-2.4 mm, 1/2 - 3/4 as long as the spikelets, attenuate;

upper glumes and lower lemmas similar, 7-11-veined, acuminate, extending 0.3-1.2 mm beyond the upper florets;

lower florets sterile;

lower paleas 0.8-2 mm;

upper florets 1.5-2.4 mm long, 0.7-1.2 mm wide, ovoid to ellipsoid, smooth, nigrescent.

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.

Terminal

panicles 7-31 cm long, 3-15 cm wide;

rachises glabrous, tending to break at maturity;

branches usually alternate, slender, stiff, ascending to divergent;

pedicels 1-15 mm, appressed.

2n

= 18.

Panicum hallii

Panicum mohavense

Distribution
from FNA
AZ; CO; LA; NM; OK; TX; UT
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; NM
[BONAP county map]
Discussion

Panicum hallii grows on sandy, gravelly, or rocky land, including roadsides, pastures, rangeland, oak and pine savannahs, chaparral, and moist areas in deserts and on mesas. Its range extends from the southwestern United States to southern Mexico.

(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.)

Key
1. Spikelets 3-4.2 mm long; panicles usually greatly exceeding the blades, with a few spikelets; blades clustered near the base of the plants, ascending, often curling at maturity
subsp. hallii
1. Spikelets 2.1-3 mm long; panicles scarcely exceeding the blades, with relatively crowded spikelets; blades not clustered near the base of the plants, lax, spreading, not curled
subsp. filipes
Source FNA vol. 25, p. 466. 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
P. amarum, P. anceps, P. antidotale, P. bergii, P. bisulcatum, P. brachyanthum, P. bulbosum, P. capillare, P. capillarioides, P. coloratum, P. dichotomiflorum, P. diffusum, P. flexile, P. ghiesbreghtii, P. gymnocarpon, P. hemitomon, P. hirsutum, P. hirticaule, P. lacustre, P. miliaceum, P. mohavense, P. obtusum, P. paludosum, P. philadelphicum, P. plenum, P. psilopodium, P. repens, P. rigidulum, P. tenerum, P. trichoides, P. urvilleanum, P. verrucosum, P. virgatum
P. amarum, P. anceps, P. antidotale, P. bergii, P. bisulcatum, P. brachyanthum, P. bulbosum, P. capillare, P. capillarioides, P. coloratum, P. dichotomiflorum, P. diffusum, P. flexile, P. ghiesbreghtii, P. gymnocarpon, P. hallii, P. hemitomon, P. hirsutum, P. hirticaule, P. lacustre, P. miliaceum, P. obtusum, P. paludosum, P. philadelphicum, P. plenum, P. psilopodium, P. repens, P. rigidulum, P. tenerum, P. trichoides, P. urvilleanum, P. verrucosum, P. virgatum
Subordinate taxa
P. hallii subsp. filipes, P. hallii subsp. hallii
Synonyms P. lepidulum
Name authority Vasey Reeder
Web links