Piptochaetium stipoides

(Trin. & Rupr.) Hack.
Common names: Stipoid ricegrass
Synonyms: Piptochaetium stipoides var. purpurascens
Treatment appears in FNA Volume 24. Treatment on page 166.
Please click on the illustration for a higher resolution version.
Illustrator: Cindy Roché

Copyright: Utah State University

Culms 20-60 cm, erect to ascending; nodes 2-4, dark, glabrous. Sheaths glabrous or hispidulous towards the collar; ligules 0.8-2 mm, glabrous, abaxial surfaces scabridulous, margins occasionally ciliate; blades (5) 14-30 cm long, 0.2-0.4 mm wide, linear, glabrous or villous, margins scabridulous. Panicles 4-15 cm long, 1.5-3 cm wide, with 10-70 spikelets; branches ascending, scabridulous; pedicels 1-11 mm, hispid. Glumes subequal, 4-8.5 mm long, 1.5-2 mm wide, purple towards the base, glabrous, 5-veined, apices aristulate; florets 2.3-4 (5) mm long, 0.8-2.3 mm thick, obovoid, globose to laterally compressed; calluses 0.5-0.6 mm, blunt, hairs white to golden tan; lemmas shiny, glabrous, striate, dark-brown to black at maturity, wholly smooth to conspicuously verrucose or sharply papillose, at least distally, constricted below the crown; crowns well-developed, 0.6-1.6 mm wide, distal margins slightly to strongly revolute, inner surfaces densely covered with hooks and hairs; awns 15-25 mm, eccentric, twice-geniculate, tardily deciduous; paleas 2.5-5 mm; lodicules 2, linear; anthers about 0.5 mm. Caryopses 1.5-2.5 mm, spherical to ellipsoid. 2n = unknown.

Distribution

Loading map...
Created with Raphaël 2.2.0

Calif.

Discussion

Piptochaetium stipoides is native to South America. There is one known population in the Flora region, in Marin County, California, which grows with P. setosum in a meadow adjacent to an old dirt road. The origin of the population is not known; it has been suggested that the seeds might have been brought in by birds, as the area was a bird refuge at one time.

The Californian plants belong to Piptochaetium stipoides (Trin. & Rupr.) Hack. var. stipoides, which differs from the only other variety recognized by Cialdella and Arriaga (1998), P. stipoides var. echinulatum Parodi, in having lemmas that are mostly smooth as well as a less revolute crown.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number.

... more about "Piptochaetium stipoides"
membranous +  and scarious +
0.5 cm5 mm <br />0.005 m <br /> - ? +
prow-tipped +  and sulcate +
awned +  and bifid +
aristulate +
Mary E. Barkworth +
- Trin. & Rupr. Hack. +
twisted +  and not branched +
1 - ? +  and 3 - ? +
eccentric +
1.5 cm15 mm <br />0.015 m <br /> - 2.5 cm25 mm <br />0.025 m <br /> +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
swelling +
14 cm140 mm <br />0.14 m <br /> - 30 cm300 mm <br />0.3 m <br /> +
not evident +
villous +  and glabrous +
convolute +  and flat +
0.02 cm0.2 mm <br />2.0e-4 m <br /> - 0.04 cm0.4 mm <br />4.0e-4 m <br /> +
scabridulous +
spikelike +
strigose +  and glabrous +
0.05 cm0.5 mm <br />5.0e-4 m <br /> - 0.06 cm0.6 mm <br />6.0e-4 m <br /> +
Stipoid ricegrass +
branching +  and not branched +
perennial +  and annual +
erect +  and ascending +
intravaginal +  and basal +
20 cm200 mm <br />0.2 m <br /> - 60 cm600 mm <br />0.6 m <br /> +
not woody +
0 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
0.23 cm2.3 mm <br />0.0023 m <br /> - 0.4 cm4 mm <br />0.004 m <br /> +
sometimes longer +
globose +  and laterally compressed +
4mm +  and 8.5mm +
subtending +
lanceolate +
subequal +
membranous +
1.5mm +  and 2mm +
white +  and golden tan +
uncinate +
0.2 cm2 mm <br />0.002 m <br /> - 0.3 cm3 mm <br />0.003 m <br /> +
solid +  and hollow +
basally concentrated +  and evenly distributed +
dark-brown +  and black +
wholly smooth +  and conspicuously verrucose or sharply papillose +
narrowed +
constricted +
coriaceous +  and indurate +
truncate +  and acute +
0.08 cm0.8 mm <br />8.0e-4 m <br /> - 0.2 cm2 mm <br />0.002 m <br /> +
membranous +
inconspicuous +
acute +  and blunt +
scabridulous +
concealed +  and prominent +
2 +  and 4 +
2 +  and 1 +
well-developed +
reduced +
0.25 cm2.5 mm <br />0.0025 m <br /> - 0.5 cm5 mm <br />0.005 m <br /> +
4cm +  and 15cm +
1.5 cm15 mm <br />0.015 m <br /> - 3 cm30 mm <br />0.03 m <br /> +
0.1 cm1 mm <br />0.001 m <br /> - 1.1 cm11 mm <br />0.011 m <br /> +
dry +  and fleshy +
not prolonged +
hispidulous +  and glabrous +
10 +  and 70 +
unisexual +  and bisexual +
laterally compressed +  and terete +
0.4 cm4 mm <br />0.004 m <br /> - 2.2 cm22 mm <br />0.022 m <br /> +
1 +  and 3 +
simple +  and compound +
2 - ? +  and 3 - ? +
Piptochaetium stipoides var. purpurascens +
Piptochaetium stipoides +
Piptochaetium +
species +
membranous +
0.1 cm1 mm <br />0.001 m <br /> - 0.3 cm3 mm <br />0.003 m <br /> +
prow-tipped +  and sulcate +
inconspicuous +
plant +  and cespitose +
aquatic +  and terrestrial +