Poa atropurpurea

Scribn.
Common names: Bernardino bluegrass
Endemic
Treatment appears in FNA Volume 24. Treatment on page 554.
Please click on the illustration for a higher resolution version.
Illustrator: Sandy Long

Copyright: Utah State University

Plants perennial; loosely tufted, rhizomatous. Basal branching extra and intravaginal. Culms 10-55 cm, erect or the bases decumbent, terete or weakly compressed; nodes terete, not exserted. Sheaths closed for about 1/3 their length, terete, smooth, glabrous, bases of basal sheaths glabrous, distal sheath lengths 1.5-7.5 times blade lengths; collars smooth, glabrous; ligules 1-2 mm, smooth or sparsely scabrous, apices truncate to obtuse; innovation blades similar to the cauline blades, adaxial surfaces nearly smooth, glabrous on and between the veins; cauline blades fairly strongly reduced in length distally, 1-3 mm wide, folded to involute, moderately thick, moderately firm, abaxial surfaces smooth, apices narrowly prow-shaped, flag leaf-blades 1-5.5 cm. Panicles 3-7 cm, erect, lanceoloid to ovoid, congested, with 20-70 spikelets; nodes with 1-2 branches; branches 0.5-3 cm, erect, terete, usually smooth, infrequently sparsely scabrous distally, with 3-12 spikelets. Spikelets 3.5-5.5 mm, lengths to 3 times widths, laterally compressed, very compact, not sexually dimorphic; florets 2-5; rachilla internodes about 0.5 mm, smooth, glabrous. Glumes broadly lanceolate, distinctly shorter than the adjacent lemmas, distinctly keeled, keels smooth or sparsely scabrous; lower glumes 3-veined; calluses glabrous; lemmas 2.5-3.5 mm, lanceolate, usually purplish, distinctly keeled, glabrous, smooth, margins glabrous, apices acute; palea keels scabrous, intercostal regions glabrous; anthers vestigial (0.1-0.2 mm) or 1.5-2 mm. 2n = 28.

Discussion

Poa atropurpurea is a rare dioecious endemic of mesic upland meadows in southern California. It is federally listed as endangered.

Selected References

None.

Lower Taxa

None.

"thin" is not a number."reduced" is not a number.No values specified."decumbent" is not a number.

... more about "Poa atropurpurea"
membranous +  and scarious +
5 cm50 mm <br />0.05 m <br /> (?) +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
scarious-hyaline +
acute +, prow--shaped +, truncate +  and obtuse +
Robert J. Soreng +
Scribn. +
1 (?) +  and 3 (?) +
straight +
basal +  and terminal +
keeled +  and rounded +
strigose +  and glabrous +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
compressed +  and terete +
swelling +
not evident +
involute +, folded +  and flat +
hispidulous +, glabrous +, scabrous +  and smooth +
0.5 cm5 mm <br />0.005 m <br /> (3 cm30 mm <br />0.03 m <br />) +
compressed +  and terete +
folded +  and involute +
Bernardino bluegrass +
unbranched +  and hollow +
compressed +  and terete +
10 cm100 mm <br />0.1 m <br /> (55 cm550 mm <br />0.55 m <br />) +
not woody +
1/4 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
sometimes longer +
2 +  and 5 +
compressed +
reduced +
2mm +  and 10mm +
1-3(5)-veined +
shorter or longer +
subtending +
keeled +  and lanceolate +
unequal +
distributed +
uncinate +
0.1 cm1 mm <br />0.001 m <br /> (?) +
0 +  and 1/6 +
Oval (?) +  and Round (?) +
hispidulous +, glabrous +, scabrous +  and smooth +
milky white +  and slightly greenish +
moderately prominent +  and prominent +
5-7(11)-veined +
keeled +  and lanceolate +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
membranous +
erose +  and entire +
colorless +  and milky white +
truncate +  and acuminate +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
membranous +
inconspicuous +
lobed +  and lanceolate +
milky white +  and slightly greenish +
not exserted +
concealed +  and prominent +
0 +  and 5 +
2 +  and 1 +
well-developed +
2-keeled +
subequal +
30 cm300 mm <br />0.3 m <br /> (?) +
usually contracted +  and loosely contracted +
lanceoloid +  and ovoid +
3 cm30 mm <br />0.03 m <br /> (7 cm70 mm <br />0.07 m <br />) +
dry +  and fleshy +
rhizomatous +  and stoloniferous +
not bulbiferous +
3 +  and 12 +
compressed +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
Gramineae +
Poa atropurpurea +
Poa subsect. Madropoa +
species +
membranous +
5-veined +  and 3-veined +
parallel +  and converging +
branching +  and rhizomatous +
aquatic +  and terrestrial +