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northern riverbank wildrye, Wiegand's wild-rye, élyme de Wiegand

Hoffmann's wheatgrass, rs wheatgrass

Habit Plants cespitose, not rhizomatous, somewhat glaucous. Plants slightly to moderately rhizomatous.
Culms

100-180(220) cm, erect;

nodes 9-16, mostly concealed by the leaf sheaths, glabrous.

54-135 cm, glabrous.

Leaves

evenly distributed;

sheaths usually glabrous, occasionally villous, often reddish brown;

auricles 1-3 mm, brown;

ligules to 1 mm;

blades (8)10-20(24) mm wide, flat, lax, dark green, adaxial surfaces usually thinly pilose, with weakly spreading hairs on the veins at least near the margins, sometimes villous or glabrous.

evenly distributed;

sheaths glabrous;

auricles absent or to 1 mm;

ligules 0.6-1 mm, truncate, erose;

blades 5-13 mm wide, flat to involute, abaxial surfaces smooth, glabrous, adaxial surfaces glabrous, veins closely spaced, all more or less equally prominent, smooth or scabrous.

Spikes

10-30 cm long, 3-5 cm wide, pendent, the bases often barely exserted, with 2 spikelets per node;

internodes 5-8(12) mm long, 0.2-0.3 mm thick at the thinnest sections, usually pubescent beneath the spikelets.

10-50 cm long, 0.8-1.8 cm wide, with 1 spikelet per node, glabrous below the spikelets;

internodes 5-8 mm long, about 0.2 mm thick, about 0.3 mm wide, both surfaces hairy, hairs 0.2-0.4 mm.

Spikelets

12-20 mm, divergent, with (3)4-6(7) florets, lowest florets functional;

disarticulation above the glumes and beneath each floret.

15-27 mm, appressed to ascending, with 5-7 florets;

rachillas scabridulous;

disarticulation above the glumes, beneath the florets.

Glumes

equal or subequal, 12-30 mm including the often undifferentiated awns, the basal 0.5-1 mm subterete and slightly indurate, glume bodies 7-12 mm long, (0.2)0.4-0.9(1.1) mm wide, linear-setiform, entire, widening or parallel-sided above the base, 1-3(5)-veined, glabrous, hispidulous or villous, especially near the margins, margins firm, awns (5)8-15(18) mm, straight or flexuous;

lemmas 10-15 mm, usually uniformly appressed-villous, rarely scabrous-hirtellous or glabrous, awns 15-25(30) mm, moderately to strongly outcurving;

paleas 9-14 mm, narrowly truncate, minutely bidentate;

anthers 2-3.5 mm.

equal, 5-11 mm long, 1.3-1.8 mm wide, stiff, lanceolate to linear-lanceolate, strongly rounded to keeled distally, keels inconspicuous and smooth on the proximal 1/3-1/2, conspicuous and with a few teeth distally, lateral veins inconspicuous, hyaline margins 0.1-0.2 mm wide, apices acuminate to awned, awns to 8 mm;

lemmas 7-12 mm, glabrous, smooth, apices unawned or awned, awns to 12 mm, straight;

paleas ciliate on the keels, apices about 0.6 mm wide;

anthers 4-7 mm.

Anthesis

from mid-July to early August.

2n

= 28.

= 42.

Elymus wiegandii

Elymus hoffmannii

Distribution
from FNA
CT; IA; KY; MA; ME; MI; MN; ND; NH; NJ; NY; PA; SD; VT; WI; WY; NB; ON; QC; SK
[WildflowerSearch map]
[BONAP county map]
from FNA
ID
Discussion

Elymus wiegandii grows in moist or damp, rich, alluvial soil, especially on sandy river terraces and in woods and thickets, primarily from Saskatchewan through much of the Great Lakes region to Nova Scotia and Connecticut. It has abnormal neocentric chromosomes with meiotic irregularities that appear to limit the fertility of its hybrids, and even some crosses within the species (Vilkomerson 1950). It may be derived from hybrids between E. canadensis (p. 303) and perhaps E. riparius (p. 302). The latter species is similar to E. wiegandii and overlaps with it in range and habitat within the Great Lakes region, where there are a few plants that appear to be hybrids between the two. Plants with scabrous-hirtellous or glabrous lemmas (E. wiegandii f. calvescens Fernald) are known from Maine and New Hampshire.

Elymus wiegandii is often confused with sympatric E. canadensis and E. diversiglumis (p. 316), but it has a distinctive robust, broad-leaved habit. It is intermediate between the two in spike density and glume development. Occasional plants with glabrous leaves and less pendent spikes suggest introgression from E. canadensis, but artificial crosses produced no fertile Fj plants (Church 1958).

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

Elymus hoffmannii was described from a breeding line of plants developed from seeds collected in Erzurum Province, Turkey by J.A. Hoffmann and R.J. Metzger (Jensen & Asay 1996). There is no information available about its native distribution. As indicated in the key, E. hoffmannii differs from E. repens (see previous) primarily in its evenly prominent, closely spaced leaf veins and, usually, in having longer awns.

The description of Elymus hoffmannii was explicitly written to encompass the cultivar 'NewHy' that is derived from an artificial cross between E. repens and Pseudoroegneria spicata (p. 281). Because of its morphological similarity to plants obtained from the Turkish seed, Jensen and Asay suggested that E. hoffmannii had a similar parentage. 'NewHy' was released as a cultivar in the 1980s. Its distribution within the Flora region is not known.

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

Source FNA vol. 24, p. 305. FNA vol. 24, p. 336.
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. 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. wawawaiensis, 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. 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. wawawaiensis, E. wiegandii, E. ×cayouetteorum, E. ×ebingeri, E. ×hansenii, E. ×palmerensis, E. ×pinalenoensis, E. ×pseudorepens, E. ×saundersii, E. ×yukonensis
Synonyms E. canadensis var. wiegandii
Name authority Fernald K.B. Jensen & Asay
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