Montana Field Guide

PLANTS: A cool season perennial grass. Plants are strongly rhizomatous, not cespitose (densely tufted). Culms grow 50-100 cm tall, 1.8-3 mm thick, and are solitary or with a few together. Sources: Barkworth in Flora of North America [FNA] 2007; Lesica et al. 2012

LEAVES: Often basally concentrated. Blades are somewhat stiff, flat to inrolled, and 3-8 mm wide. Cultivated plants may have leaves to 10 mm wide. Sheaths are glabrous or hairs (1 mm or less tall). Auricles to 1 mm tall, Ligules to 1.3 mm tall, truncate, and erose. Top of leaf is usually scabrous and often sparsely. Veins are 11-27 in number, closely spaced, subequal, and prominent. Sources: Barkworth in FNA 2007; Lesica et al. 2012.

INFLORESCENCE: A spike - erect, continuous with the rachis, and 5-14 cm long. Internodes mostly glabrous and spaced 5-11.5 mm apart. Spikelets usually two per node, especially at mid-spike, 10-18 mm long. Glumes 5-16 mm long and linear, with a very narrow pointed tip (1-veined and tapers to mostly an awn (subulate) tip). Tapering begins from belong mid-length; central portion is thicker than margins. Veins are inconspicuous at mid-length. Bases of glumes do not overlap, 0.5-1.2 mm wide. Lemmas are 3-8 per spikelet, mostly hairless, and tapered to an awn tip or with a short, less than 3 mm long tip. Sources: Barkworth in FNA 2007; Lesica et al. 2012.

Flowers late May to August (Cronquist et al. 1977).

At initial appearance Elymus triticoides appears similar to Agropyron smithii.

Beardless Wildrye - Elymus triticoides, native, SOC
*Glumes: Linear to subulate. Tapering from below mid-length into a very narrow pointed tip. Their midribs not aligned with the lemma's midrib; thus, florets are twisted about 90 degrees out of alignment with the glumes, which is a feature that traditionally separates Elymus from Agropyron).
*Spikelets always paired at mid-spike; occasionally with 1 or 3 at bottom or top of spike.

Western Wheatgrass - Elymus smithii, native
*Glumes: rigid and gradually tapering to a narrow sharp tip, which is often curved; their midribs usually aligned with the lemma's midrib.
*Spikelets mostly singular at mid-spike; occasionally with paired spikelets.

TAXONOMY
The treatment of perennial grasses that belong to the Triticeae Tribe is contentious among botanists.

In the Manual of Montana Vascular Plants (Lesica et al. 2012) Lavin's treatment is more traditional, which focuses heavily on morphology:

Agropyron includes native and cultivated grasses that have spikes, usually 1 spikelet per node, several florets per spikelet, and have relatively broader glumes where the mid-ribs of glumes and lemmas align.

Elymus includes native and cultivated grasses that have spikes, having 2 or more spikelets per node where at least 2 spikelets are fertile, and/or having sharp-pointed glumes that do not align with the florets.

In the Flora of North America (2007) Barkworth's treatment is influenced by various genetic research and the works of Love (1984) and Dewey (1984) and remains partially contentious. Agropyron and Elymus are split into 4 genera:

Agropyron is restricted to members with keeled glumes, are called the English Crested Wheatgrasses, and includes only the species Agropyron cristatum.

Leymus are categorized as alkaline tolerant grasses that are strongly rhizomatous or have short, subulate glumes.

Pascopyrum is categorized as being a North American allooctoploid, which includes only the species Pascopyrum smithii.

Pseudoroegneria species are categorized as being obligate outcrossers and have a genome that is either diploid or autotetraploid and also contains the "St" haplome. The only North American species is Pseudoroegneria spicata.

Open, dry moderately disturbed sites at lower elevations (Lesica et al. 2012). Dry to moist, often saline meadows (Barkworth in FNA 2007).

WILDLIFE INTERACTIONS
Wet meadows dominated by Beardless Wildrye provide habitat to nesting and foraging birds (Kilbride et al. 1997). In dry meadows this plant provides habitat for a variety of small mammals (McAdoo et al. 2006).

CULTURAL USES
Beardless Wildrye seeds can be ground into a flour for baking and cooking (Moerman 1998). Leaves can be used to make baskets, ropes, and other fibrous products (Moerman 1998).

Plants reproduce from seed and rhizomes.

FLOWERS
Anthers are 3-6mm and dehiscent.

Beardless Wildrye’s strong and extensive creeping rhizomes and tolerance to lengthy flooding make it valuable in stabilizing stream bottoms and banks (USDA-NRCS 1991). Wet meadows dominated by Beardless Wildrye afford habitat to nesting and foraging birds (Kilbride et al. 1997). Various rodents make use of habitat that dry meadows with an abundance of this species offer (McAdoo et al. 2006). It provides fair forage for livestock, particularly in early spring while it is still tender (Cronquist 1977). Other uses of Beardless Wildrye include grinding seeds to prepare flour for baking and cooking, and fashioning leaves into baskets, ropes, and other fibrous products (Moerman 1998).

BREVEGETATION
Beardless Wildrye’s strong and extensive creeping rhizomes and tolerance to pro-longed flooding makes it valuable in stabilizing stream bottoms and banks (USDA-NRCS 1991).

Beardless Wildrye may be grown from rhizome plugs or be seeded. Establishing stands from seed can be challenging because it has a high dormancy rate (Knapp and Wiesner 1978). In northern latitudes, seed dormancy rates can be broken by over-wintering; thus, seeding should occur in the fall. Reducing competition from weeds will improve seedling establishment. Once established, stands of Beardless Wildrye will live for many years (Young-Mathews and Winslow 2010).

NUTRITION - LIVESTOCK
Beardless Wildrye provides fair forage for livestock, particularly in early spring when it is tender (Cronquist et al. 1977).

STATE THREAT SCORE REASON
Threat impact not assigned because threats are not known (MTNHP Threat Assessment 2021).