Elymus stebbinsii
Elymus ×pseudorepens
Parish wheatgrass, Stebbins' wheat grass, Stebbins' wildrye
false quackgrass
60-140 cm;
nodes glabrous or retrorsely pubescent.
30-100 cm, ascending or erect, glabrous, mostly smooth, sometimes scabrous below the nodes.
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.
evenly distributed;
sheaths glabrous;
ligules to 0.5 mm;
blades 10-25 cm long, 2-7 mm wide, involute when dry, both surfaces scabrous, adaxial surfaces sparsely pilose, hairs 0.7-1 mm.
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.
5.5-13 cm long, 0.4-0.6 cm wide, with 1 spikelet per node;
internodes 3.5-5 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.
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.
8-18 mm, equaling or exceeded by the adjacent lemmas, more or less flat, 5-9-veined, margins unequal, the wider margins to about 0.3 mm, narrowly acute, sometimes awned, awns to 1 mm;
lemmas 7.5-15 mm, smooth and glabrous proximally, scabrous distally, mucronate or awned, awns to 3 mm;
anthers 1.5-2 mm.
= 28.
Elymus stebbinsii
Elymus ×pseudorepens
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 ×pseudorepens consists of hybrids between E. lanceolatus (p. 327) and E. trachycaulus (p. 321). It appears to be fairly common, having been reported from Alberta to Michigan and south to Arizona, New Mexico, and Arkansas.
Elymus ×pseudorepens 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
WA
Flora NW
PNW Herbaria
