Jarava ichu

Ruiz & Pav.
Common names: Peruvian needlegrass
Treatment appears in FNA Volume 24. Treatment on page 179.

Plants densely cespitose, not rhizomatous. Culms (15) 30-100 cm, bases dull brown, glabrous; nodes 2-4; branching intravaginal. Sheaths mostly glabrous, scabridulous, basal sheaths dull brown; ligules 0.3-1 mm, truncate, erose, abaxial surfaces glabrous or almost so, ciliate, hairs longest (to 2 mm) towards the sides of the leaves, at the top of the sheaths; blades (3) 10-40 cm long, 0.5-1 mm wide, all alike, straight, erect, convolute, apices sharp. Panicles (3) 10-25 (30) cm, narrow, cylindrical to lanceoloid, dense, from partially to wholly exserted at anthesis, erect or nodding distally; branches strongly ascending. Spikelets 5.5-11 mm. Glumes subequal, clearly exceeding the florets, linear-lanceolate, tapering to attenuate apices; lower glumes 5.5-11 mm, 1-3-veined; upper glumes 5-10.5 mm, 3-veined; florets 2.3-3 mm, cylindrical to fusiform; calluses 0.2-0.4 mm, acute to broadly acute, strigose; lemmas hairy throughout, hairs on the lower portion about 0.15 mm, sparse, appressed, pappus hairs 3-4 mm; awns 9-15 mm, twice-geniculate, first 2 segments twisted, scabridulous; paleas 1-1.5 mm, sparsely pubescent, 2-veined, apices rounded; lodicules 2, 0.6-1 mm; anthers about 0.8 mm. Caryopses 1.8-2.2 mm long, 0.6-0.7 mm thick, cylindrical.

Discussion

Jarava ichu is native to Mexico, Costa Rica, Venezuela, Colombia, Ecuador, Peru, Bolivia, and Argentina. It is abundant in much of this range. In the Flora region, it is sold as an attractive ornamental. The species could become a problem, because it is self-compatible and produces a large quantity of wind-dispersed seeds. In parts of its native range, J. ichu is highly valued for its ability to prevent soil erosion, and for its use in thatch, mats, and basketry. "Ichu" is a term used to describe any bunchgrass in some parts of South America.

Selected References

None.

Lower Taxa

None.

"decumbent" is not a number."prolonged" is not a number.

... more about "Jarava ichu"
almost +  and glabrous +
membranous +  and scarious +
0.8 cm8 mm <br />0.008 m <br /> (?) +
awned +, bifid +, bilobed +  and entire +
rounded +  and sharp +
Mirta O. Arriaga +
Ruiz & Pav. +
twisted +  and not branched +
1 (?) +  and 3 (?) +
80 cm800 mm <br />0.8 m <br /> (?) +
subterminal +  and eccentric +
pilose +  and scabrous +
scabridulous +
0.9 cm9 mm <br />0.009 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
keeled +  and rounded +
pseudopetiolate +  and branching +
intravaginal +, extravaginal +, branching +  and basal +
knotted +
swelling +
straight +
10 cm100 mm <br />0.1 m <br /> (40 cm400 mm <br />0.4 m <br />) +
not evident +
cross +, linear +  and narrowly lanceolate +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
spikelike +
well-developed +
acute +  and broadly acute +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.04 cm0.4 mm <br />4.0e-4 m <br />) +
Peruvian needlegrass +
not branching +
perennial +  and annual +
ascending +  and erect +
extravaginal +, intravaginal +, branching +  and basal +
30 cm300 mm <br />0.3 m <br /> (100 cm1,000 mm <br />1 m <br />) +
not woody +
0 +  and 1/3 +
liquid +, soft +  and hard +
capillary +
pistillate +  and staminate +
sometimes longer +
cylindrical +  and fusiform +
2.3mm +  and 3mm +
1-10-veined +
usually longer +
subtending +
tapering +  and attenuate +
subequal +
membranous +
longest +
uncinate +
1 cm10 mm <br />0.01 m <br /> (?) +
solid +  and hollow +
basally concentrated +  and evenly distributed +
10 cm100 mm <br />0.1 m <br /> (?) +
1/3 +  and 2/3 +
ovate +, rectangular +  and lanceolate +
0.3 cm3 mm <br />0.003 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
membranous +
hairy +  and glabrous +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
membranous +
inconspicuous +
lanceolate +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
fleshy +  and membranous +
0.55 cm5.5 mm <br />0.0055 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
0.15 cm1.5 mm <br />0.0015 m <br /> (?) +
intravaginal +
concealed +  and prominent +
2 +  and 4 +
2 +  and 1 +
pubescent +  and glabrous +
well-developed +
1/3 +  and 1/2 +
reduced +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
membranous +
3 cm30 mm <br />0.03 m <br /> (?) +
nodding +  and erect +
cylindrical +  and lanceoloid +
10 cm100 mm <br />0.1 m <br /> (25 cm250 mm <br />0.25 m <br />) +
dry +  and fleshy +
not prolonged +
scabridulous +
1 +  and 60 +
unisexual +  and bisexual +
laterally compressed +  and terete +
0.55 cm5.5 mm <br />0.0055 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
1 +  and 3 +
simple +  and compound +
2 (?) +  and 3 (?) +
Gramineae +
Jarava ichu +
species +
membranous +
0.5 cm5 mm <br />0.005 m <br /> (1.05 cm10.5 mm <br />0.0105 m <br />) +
inconspicuous +
plant +  and cespitose +
aquatic +  and terrestrial +
12 +, 11 +, 10 +, 8 +  and 7 +