Jarava speciosa
Jarava ichu
desert needlegrass
Peruvian needlegrass
30-60 cm, bases orange-brown;
nodes 3-6;
basal branching intravaginal.
(15)30-100 cm, bases dull brown, glabrous;
nodes 2-4; branching intravaginal.
mostly glabrous, throats densely ciliate, basal sheaths reddish brown, flat and ribbonlike with age;
ligules varying within a plant, lower ligules 0.3-1 mm, densely hairy and ciliate, hairs 0.2-1 mm, often longer than the basal membrane, upper ligules to 2.5 mm, hyaline to scarious, glabrous or hairy, usually less hairy than the lower ligules, sometimes ciliate;
blades 10-30 cm long, 0.5-2 mm wide when flat, usually rolled, to 1 mm in diameter, abaxial surfaces glabrous, smooth, adaxial surfaces pilose.
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.
10-15 cm, dense, frequently partially included in the upper leaf sheaths at maturity;
branches ascending.
(3)10-25(30) cm, narrow, cylindrical to lanceoloid, dense, from partially to wholly exserted at anthesis, erect or nodding distally;
branches strongly ascending.
16-24 mm.
5.5-11 mm.
linear-lanceolate, glabrous, tapering from below midlength to the narrowly acute apices;
lower glumes 16-24 mm, 1-veined;
upper glumes 13-19 mm, 3-5-veined;
florets (6)8-10 mm;
calluses 0.8-1.6(3) mm, sharp;
lemmas densely and evenly hairy, hairs about 0.5 mm, without a pappus;
awns 35-45(80) mm, once-geniculate, first segment pilose, hairs 3-8 mm, terminal segment glabrous, smooth;
paleas 3.2-5.1 mm, 2/5 – 2/3 (4/5) the length of the lemmas, usually hairy, hairs about 0.5 mm.
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.
1.8-2.2 mm long, 0.6-0.7 mm thick, cylindrical.
= 66, 68, about 74.
Jarava speciosa
Jarava ichu
Jarava speciosa grows on rocky slopes in canyons of arid and semiarid regions of the southwestern United States and northern Mexico, and in Chile and northern to central Argentina. Several varieties are recognized in South America. It is not clear to which of these varieties, if any, the North American plants belong.
The reddish brown leaf bases, differing lower and upper ligules, and the pilose, once-geniculate awns make Jarava speciosa an easy species to recognize in North America. It is also an attractive species, well worth cultivating. It prefers open areas with well-drained soils. The growth of young shoots and flowering is stimulated by fire.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
CA
OR
Flora NW
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
