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bottlebrush grass, eastern bottle-brush grass, glumeless wlldrye

Snake River wheatgrass, wawawai wild rye

Habit Plants cespitose, not rhizomatous, occasionally glaucous, particularly the spikes. Plants cespitose, sometimes weakly rhizomatous.
Culms

50-140 cm, usually erect, occasionally geniculate below;

nodes 4-8, exposed or concealed, glabrous.

(15)50-130 cm, erect, mostly glabrous;

nodes usually glabrous, sometimes slightly pubescent.

Leaves

evenly distributed;

sheaths usually glabrous, occasionally pilose, often purplish;

auricles usually present, 0.5-3 mm, brown to black;

ligules 1-2(3) mm;

blades 4-16 mm wide, lax, usually deep glossy green, adaxial surfaces pilose or scabridulous.

more or less evenly distributed;

basal sheaths glabrate, margins not evidently ciliate;

auricles absent or to 1.2 mm;

ligules 0.1-1.1 mm;

blades to 28 cm long, 1.7-5 mm wide, involute when dry, adaxial surfaces usually densely pubescent, rarely sparsely pubescent.

Spikes

7-20 cm long, 4-7 cm wide, more or less erect, usually with 2 spikelets per node, rarely with 3 at some nodes;

internodes (3)4-8(10) mm long, (0.1)0.2-0.3(0.4) mm thick at the thinnest sections, flexuous, usually glabrous, sometimes scabrous or hirsute, usually with green lateral bands.

5-20 cm long, 2.5-3 cm wide including the awns, erect to slightly nodding, with 1 spikelet per node;

internodes 5-12 mm long, about 0.2 mm thick, about 0.3 mm wide, glabrous beneath the spikelets.

Spikelets

10-18 mm, strongly divergent to patent at maturity, with (1)2-4(6) florets, lowest florets functional;

disarticulation above the glumes, beneath each floret.

10-22 mm long, about twice as long as the internodes, 2-8.5 mm wide, appressed, with 4-10 florets;

rachillas glabrous;

disarticulation above the glumes, beneath each floret.

Glumes

usually vestigial, sometimes 1-3 mm long, about 0.1 mm wide, subulate, entire, with no evident veins, occasionally to 10(20) mm long including the undifferentiated awns and differing in length by more than 5 mm, 0.1-0.2 mm wide, setaceous, tapering from the base, usually glabrous, occasionally appressed-puberulent to strigose, sometimes scabrous, usually straight, rarely somewhat curving, margins firm;

lemmas 8-11 mm, usually glabrous, occasionally appressed-puberulent to strigose, especially near the margins and apices, awns (12)20-40(47) mm, usually straight, rarely somewhat curving;

paleas 7-11 mm, obtuse or truncate, occasionally emarginate;

anthers 2.5-5 mm.

4-10 mm long, 0.5-1.3 mm wide, narrowly lanceolate, widest at or below midlength, glabrous, often glaucous, 1-3-veined, flat or weakly keeled, margins 0.1-0.2 mm wide, widest near midlength, apices usually acuminate, awned or unawned, awns to 6 mm;

lemmas 6-12 mm, smooth or slightly scabrous, margins often sparsely pubescent proximally, apices awned, longest awns in the spikelets 9-28 mm, strongly divergent;

paleas 7.2-10.5 mm, keels scabrous distally, tapering to the 0.2-0.3 mm wide apices;

anthers 3.5-6 mm.

Anthesis

mid-June to early July.

2n

= 28.

= 28.

Elymus hystrix

Elymus wawawaiensis

Distribution
from FNA
AL; AR; CT; DC; DE; GA; IA; IL; IN; KS; KY; MA; MD; ME; MI; MN; MO; NC; ND; NE; NH; NJ; NM; NY; OH; OK; PA; RI; SC; SD; TN; VA; VT; WI; WV; MB; NB; NS; ON; QC
[WildflowerSearch map]
[BONAP county map]
from FNA
ID; OR; WA
[BONAP county map]
Discussion

Elymus hystrix grows in dry to moist soils in open woods and thickets, especially on base-rich slopes and small stream terraces. It grows throughout most of temperate eastern North America, extending west to Manitoba and Oklahoma, but is absent from the southern portion of the coastal plain.

Plants with pubescent lemmas have been recognized as Elymus hystrix var. bigelovianus (Fernald) Bowden. These occur infrequently north of a line from South Dakota through Kentucky to New Jersey, and are often mixed with the typical variety; uniform populations are known in the northeastern United States. Plants with pubescent blades are also more prevalent to the north. Elymus hystrix hybridizes with most eastern species of Elymus. Introgression may account for the considerable variation in glume development and spikelet appression among these species. Lack of glumes may be a recessive character, with even slight glume development indicating introgression (Church 1967b). Plants with relatively well-developed, subequal glumes are presumed to be of hybrid origin. Such plants include most material from the Carolina piedmont region, where E. glabriflorus (p. 296) is the most likely source of introgression. The relatively frequent hybrids with E. virginicus (p. 298) are usually sterile, but Church (1967b) made crosses through three segregating generations. Within the ranges of E. diversiglumis (p. 316), E. svensonii (p. 314), and E. churchii (p. 314;, there appear to be frequent introgressants between these species and E. hystrix. Further east, especially in the Appalachian regions of North Carolina, Virginia, West Virginia, and Maryland (including the shale barrens and nearby), there are scattered plants of E. hystrix with curving awns and, in a few cases, appressed spikelets (Campbell 2002). Whether these represent occasional variation within the E. hystrix gene pool, or whether they are outlying remnants of introgression with E. canadensis (p. 303) during a past eastward extension, is unknown.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Elymus wawawaiensis grows primarily in shallow, rocky soils of slopes in coulees and reaches of the Salmon, Snake, and Yakima rivers of Washington, northern Oregon, and Idaho. There are also a few records from localities at some distance from the Snake River and its tributaries. These probably reflect deliberate introductions. C.V. Piper, who worked for the U.S. Department of Agriculture in southeastern Washington from 1892-1902, frequently distributed seed to farmers in the region from populations that he considered superior; he considered E. wawawaiensis to be a superior form of what is here called Pseudo-roegneria spicata (p. 281). Another source of introduced populations is 'Secar', a cultivar of E. wawawaiensis that is recommended as a forage grass for arid areas of the northwestern United States.

Elymus wawawaiensis resembles a vigorous version of Pseudoroegneria spicata, and was long confused with that species. It differs in its more imbricate spikelets and narrower, stiff glumes. In its primary range, E. wawawaiensis is often sympatric with P. spicata, but the two tend to grow in different habitats, E. wawawaiensis growing in shallow, rocky soils and P. spicata in medium- to fine-textured loess soil. The two species also differ cytologically, E. wawawaiensis being an allo-tetraploid, and P. spicata consisting of diploids and autotetraploids.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 24, p. 316. FNA vol. 24, p. 332.
Parent taxa Poaceae > subfam. Pooideae > tribe Triticeae > Elymus Poaceae > subfam. Pooideae > tribe Triticeae > Elymus
Sibling taxa
E. alaskanus, E. albicans, E. arizonicus, E. bakeri, E. canadensis, E. caninus, E. churchii, E. ciliaris, E. curvatus, E. dahuricus, E. diversiglumis, E. elymoides, E. glabriflorus, E. glaucus, E. hirsutus, E. hoffmannii, E. interruptus, E. lanceolatus, E. macgregorii, E. macrourus, E. multisetus, E. pringlei, E. repens, E. riparius, E. scribneri, E. semicostatus, E. sibiricus, E. sierrae, E. stebbinsii, E. svensonii, E. texensis, E. trachycaulus, E. tsukushiensis, E. villosus, E. violaceus, E. virginicus, E. wawawaiensis, E. wiegandii, E. ×cayouetteorum, E. ×ebingeri, E. ×hansenii, E. ×palmerensis, E. ×pinalenoensis, E. ×pseudorepens, E. ×saundersii, E. ×yukonensis
E. alaskanus, E. albicans, E. arizonicus, E. bakeri, E. canadensis, E. caninus, E. churchii, E. ciliaris, E. curvatus, E. dahuricus, E. diversiglumis, E. elymoides, E. glabriflorus, E. glaucus, E. hirsutus, E. hoffmannii, E. hystrix, E. interruptus, E. lanceolatus, E. macgregorii, E. macrourus, E. multisetus, E. pringlei, E. repens, E. riparius, E. scribneri, E. semicostatus, E. sibiricus, E. sierrae, E. stebbinsii, E. svensonii, E. texensis, E. trachycaulus, E. tsukushiensis, E. villosus, E. violaceus, E. virginicus, E. wiegandii, E. ×cayouetteorum, E. ×ebingeri, E. ×hansenii, E. ×palmerensis, E. ×pinalenoensis, E. ×pseudorepens, E. ×saundersii, E. ×yukonensis
Synonyms Hystrix patula var. bigeloviana, Hystrix patula, E. hystrix var. bigelovianus
Name authority L. J.R. Carlson & Barkworth
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