Elymus stebbinsii
Elymus ×cayouetteorum
Parish wheatgrass, Stebbins' wheat grass, Stebbins' wildrye
wildrye
60-140 cm;
nodes glabrous or retrorsely pubescent.
to 1 m tall, about 4 mm thick.
evenly distributed;
sheaths glabrous or pubescent;
auricles usually present, 0.5-2 mm;
ligules 0.3-3.5 mm, truncate to acute, sometimes long-ciliate;
blades 4-6.5 mm wide, flat or the margins involute, straight.
not basally concentrated;
sheaths smooth;
ligules about 0.5 mm, glabrous;
blades 20-30 cm long, about 10 mm wide, both surfaces scabrous.
15-31 cm long, 0.4-1.5 cm wide including the awns, 0.4-0.8 cm wide excluding the awns, erect, with 1 spikelet per node;
internodes 9-27 mm long, 1-1.3 mm wide, glabrous, smooth.
about 25 cm, lower nodes with 1 spikelet, most middle to upper nodes with 2;
internodes about 18 mm.
13-29 mm long, from shorter than to almost twice as long as the internodes, 2.5-5 mm wide, appressed, with 5-7 florets;
rachillas glabrous;
disarticulation above the glumes and beneath each floret.
about 40 mm including the awns, about 20 mm excluding the awns, appressed, with 5-8 florets.
subequal, 7.5-12 mm long, 1.2-1.5 mm wide, lanceolate, widest at about mid-length, flat or rounded on the back, 5-veined, veins smooth, scabrous or just the midvein scabridulous, margins widest at about midlength, apices acute, unawned;
lemmas 9-12 mm, glabrous, sometimes scabrous, acute, unawned or awned, awns to 28 mm, straight;
paleas subequal to the lemmas, tapering, apices 0.2-0.3 mm wide;
anthers (3.5)4-7 mm.
12-15 mm, not or scarcely indurate, mostly smooth, veins scabrous, awns 3-5 mm;
lemmas about 14 mm, glabrous, awns 18-22 mm, not to moderately divergent;
anthers 1.8-2 mm, indehiscent.
= 28.
Elymus stebbinsii
Elymus ×cayouetteorum
Elymus stebbinsii is restricted to California, where it grows on dry slopes, chaparral, and wooded areas, at elevations below 1600 m. It differs from other Elymus species primarily in its combination of long anthers and solitary spikelets. It is often confused with E. glaucus (p. 306) and E. trachycaulus (p. 321) with solitary spikelets. It differs from both in its longer anthers, and from most representatives of E. glaucus in its acute, but unawned, glumes.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Elymus ×cayouetteorum consists of hybrids between E. trachycaulus (p. 321) and E. canadensis (p. 303). The above description is based on the type specimen, which was collected on the Ilets Jeremie, Quebec. It is not known how widespread such hybrids are.
Elymus ×cayouetteorum is an Elymus named hybrid
Elymus is notorious for its ability to hybridize. Most of its interspecific hybrids are partially fertile, permitting introgression between the parents. The descriptions provided below are restricted to the named interspecific hybrids. They should be treated with caution and some skepticism; some are based solely on the type specimen, because little other reliably identified material was available. Moreover, as the descriptions of the non-hybrid species indicate, many other interspecific hybrids exist.
The parentage of all hybrids is best determined in the field. Perennial hybrids, such as those in Elymus, can persist in an area after one or both parents have died out, but the simplest assumption is that both are present. Interspecific hybrids of Elymus that have disarticulating rachises presumably have E. elymoides or E. multisetus as one of their parents.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Lemmas awned, awns 8-28 mm long; lower leaf sheaths rarely pubescent; spikelets 13-22 mm long | subsp. septentrionalis |
1. Lemmas unawned or with awns to 8(12) mm long; lower leaf sheaths pubescent or glabrous; spikelets 17-29 mm long | subsp. stebbinsii |
CA
WildflowerSearch
iNaturalist
USDA Plants Database
