Slender Wheatgrass

Slender wheat grass is suitable for post wildfire and site rehabilitation when there is native plant community objective. Tolerance for alkaline soils with pH up to 9.0. Good seedling vigor but it is not long lived, and so should be seed in a mix with other native species. Varieties have been developed. Where there is a native plant community objective, and a desire to maintain a high level of ecological integrity, seed from local ecotypes or wild populations may be preferred.

General Description:

Slender wheatgrass is a cool season, native perennial bunchgrass. Its roots are fibrous, sometimes with short rhizomes.

This grass has a wide geographic distribution throughout North America. Like bluebunch wheatgrass, two subspecies occur in British Columbia. The awned version, Elymus trachycaulus ssp. subsecundus (Link) A. Love & D. Love, occurs more frequently in southern British Columbia, while the awnless plant (Elymus trachycaulus (Link) Gould ex Shinners ssp. trachycaulus) is prevalent through most of the province.

Awnless slender wheatgrass was propagated for seed production by the 1920s on the prairies and was known as western ryegrass. It was an important forage species until the introduction of crested wheatgrass in the 1930s.

Stems typically range from 30 to120 cm (12 to 47 in.). It has leaves that are usually flat. Seed heads are slender and 8 to 20 cm (3 to 8 in.) long with overlapping spikelets. Spikelets are awned or awnless as noted in description above.

Origin:

Native to North America

Distribution:

Slender wheatgrass is common throughout British Columbia and much of North America.

Habitat and climate:

It occupies moderately moist to dry grasslands, meadows, forest openings, rocky ridges, and slopes throughout British Columbia and all vegetation zones.

Uses:

Slender wheatgrass is utilized by both livestock and wildlife. Under optimal conditions it may also be harvested for hay. It has been used widely in both restoration and reclamation situations, in part because seedling vigour is better than other native grasses. It is quick to germinate, so that it also has some application for erosion control. It has been used for post- wildfire restoration, mine reclamation, and seeding of roadside right-of-ways and other disturbances.

Optimal time of grazing use:

Slender wheatgrass can be grazed at the 4-leaf stage, but should be grazed only once per year. It maintains growth into summer, cures fairly well, and can be grazed in fall and winter.

Recovery after use (rating):

Recovery after use:

Slender wheatgrass is considered excellent forage but has low tolerance to heavy or repeated grazing.

Forage yield (rating):

Forage yield:

Yield is variable depending on the site and establishment conditions. Yields of 5,170 kg/ha (4,616 lb/acre) can be expected in agronomic situations with good soil and moisture conditions.

Palatability/Nutritional Value:

Slender wheatgrass has average digestibility and crude protein ranging from 11% before heading to 9.5% at maturity.

Longevity (rating):

Longevity:

Slender wheatgrass is considered relatively short lived (3-4 years). In seeded applications it is sometimes used as an interim species in mixtures that include longer-lived, slower-establishing species.

Persistence (rating):

Persistence:

Seed production and drop should be allowed at least every other year, to increase persistence.

Invasiveness (rating):

Invasiveness:

In some regions slender wheatgrass has so well established that it is considered a vigorous persistent weed.

Competitiveness (rating):

Competitiveness:

Slender wheatgrass generally decreases in abundance, but because of early seedling vigour seeding rate should be limited to roughly 1 kg/ ha (around 1 lb of PLS per acre) in mixes where slower to establish species are used.

Weed resistance (rating):

Weed resistance:

Because it is quick to establish, slender wheatgrass may be useful for reducing weedy species if applied immediately after disturbance.

Erosion control (rating):

Erosion control:

Because it is quick to establish and has good seedling vigour, slender wheatgrass is often used in erosion control applications. Inclusion of longer-lived species is recommended for long-term stabilization.

Drought tolerance (rating):

Drought tolerance:

Slender wheatgrass has fair drought tolerance.

Winter hardiness (rating):

Winter hardiness:

Slender wheatgrass has good winter hardiness.

Soil texture preference (rating):

Soil texture preference:

Slender wheatgrass prefers fine- to moderately-textured soils.

Flooding tolerance (rating):

Flooding tolerance:

Slender wheatgrass is well suited to drained low lying areas, but can stand spring flooding of 2-5 weeks.

Salinity tolerance (rating):

Salinity tolerance:

Slender wheatgrass has good salinity tolerance and is often used for reclamation on saline soils.

Acidity tolerance (rating):

Acidity tolerance :

Slender wheatgrass can tolerate soil pH levels as low as 5.6.

Pests and/or disease threats:

Slender wheatgrass is susceptible to head smut (Ustilago bullata) and stripe smut (U. striiformis) and may be susceptible to infestations of grass billbug.

Ease of establishment (rating):

Ease of establishment:

Slender wheatgrass establishes easily. “Adanac” and “Revenue” are two common Canadian varieties and were both developed in Saskatchewan by Agriculture Canada. The Alberta Environmental Centre released “AEC Hillcrest” in 1994. This variety originates from the awned subspecies, and is expected to be suited to more difficult site conditions and shorter growing seasons.

Application requirements:

In field situations, a firm weed free seed bed and a seeding rate of approximately 7 kg/ha (approx. 6 lb/acre of PLS or pure live seed per acre) are recommended. Seeding depth should be 0.6 to 2 cm (1/4 to 3/4 in.). In restoration and erosion control, or other broadcast seeded applications, a seeding rate of 1.5 to 2 times the drill seeded rate is recommended. Seeding rate should be reduced to 1 kg/ha (approx.1 lb PLS per acre) when combined with slower establishing native species to reduce seedling competition.

Suggested mixtures:

Slender wheatgrass is often included in seed mixes, with slower-establishing, longer-lived species.

Management considerations:

In situations where slender wheatgrass is grazed by livestock, rest or deferment every 2-3 years should maximize persistence.