Aristida purpurea var. parishii

(Hitchc.) Allred
Common names: Parish's threeawn
Synonyms: Aristida wrightii var. parishii Aristida parishii
Treatment appears in FNA Volume 25. Treatment on page 333.

Culms 20-50 cm. Leaves mostly cauline; blades more than 10 cm, loosely involute to flat. Panicles 15-24 cm; primary branches stiff, lower branches strongly divergent to divaricate, with axillary pulvini, upper branches appressed to ascending, without axaillary pulvini, lower nodes associated with 8-18 spikelets. Glumes red or dark at anthesis, fading to stramineous; lower glumes 7-11 mm, 3/4 as long as to equaling the upper glumes; upper glumes 10-15 mm; lemmas 10-13 mm long, narrowing to 0.2-0.3 mm wide near the apex; awns subequal, 20-30 mm long, 0.2-0.3 mm wide at the base. 2n = unknown.

Discussion

Aristida purpurea var. parishii grows on sandy plains and hills of the southwestern United States and Baja California, Mexico. In many respects it is intermediate between A. purpurea and other species of Aristida with spreading panicle branches, especially A. ternipes var. gentilis. Its spikelets are indistinguishable from those of var. wrightii, but var. parishii frequently has axillary pulvini associated with the lower branches. The two also differ in their phenology: var. parishii flowers from March through May in response to winter rains, whereas var. wrightii flowers from May through October in response to summer rains.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

88 +, 66 +, 44 +  and 22 +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.1mm;0.8mm +
Kelly W. Allred +
(Hitchc.) Allred +
not disarticulating +
divaricate +
1 (?) +  and 3 (?) +
8 cm80 mm <br />0.08 m <br /> (?) +
straight +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
not conspicuous +
subequal +
1.3 cm13 mm <br />0.013 m <br /> (14 cm140 mm <br />0.14 m <br />) +
0.2mm;0.3mm +
keeled +  and rounded +
coiled +, disarticulating +  and twisted +
spreading +  and appressed +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
straight +
0 cm0 mm <br />0 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
4 cm40 mm <br />0.04 m <br /> (25 cm250 mm <br />0.25 m <br />) +
scabridulous +
loosely involute +  and flat +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
spikelike +
well-developed +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.18 cm1.8 mm <br />0.0018 m <br />) +
tan +  and chestnut +
0.6 cm6 mm <br />0.006 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
non-radiate +  and radiate +
pilose +  and glabrous +
Parish's threeawn +
erect +  and ascending +
20 cm200 mm <br />0.2 m <br /> (50 cm500 mm <br />0.5 m <br />) +
not woody +
Calif. +, Ariz. +  and Nev. +
large +  and small +
thread-like +
capillary +
germination +
pistillate +  and staminate +
sometimes longer +
compressed +  and terete +
fading +  and stramineous +
subtending +
acute +  and acuminate +
unequal +
straight +
3 cm30 mm <br />0.03 m <br /> (?) +  and 30 cm300 mm <br />0.3 m <br /> (?) +
2 cm20 mm <br />0.02 m <br /> (12 cm120 mm <br />0.12 m <br />) +
1.3 cm13 mm <br />0.013 m <br /> (14 cm140 mm <br />0.14 m <br />) +
whitish +  and purplish +
1 cm10 mm <br />0.01 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
tuberculate +  and scabridulous +
fusiform +
0.6 cm6 mm <br />0.006 m <br /> (1.6 cm16 mm <br />0.016 m <br />) +
coriaceous +
wide +  and narrowing +
indistinguishable +
0 cm0 mm <br />0 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
inconspicuous +
scabridulous +  and smooth +
0.7 cm7 mm <br />0.007 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
concealed +  and prominent +
with straight +  and glabrous +
2 +  and 1 +
concealing +
0 +  and 1/2 +
15 cm150 mm <br />0.15 m <br /> (24 cm240 mm <br />0.24 m <br />) +
dry +  and fleshy +
ascending;usually appressed;ascending +
3 cm30 mm <br />0.03 m <br /> (6 cm60 mm <br />0.06 m <br />) +
not prolonged +
not disintegrating +
shorter or longer +
1 (?) +  and Anatomy (?) +
8 +  and 18 +
1 +  and 3 +
triangular +  and dome--shaped +
2 (?) +  and 3 (?) +
Aristida wrightii var. parishii +  and Aristida parishii +
Aristida purpurea var. parishii +
Aristida purpurea +
variety +
membranous +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
plant +  and cespitose +
aquatic +  and terrestrial +