Bluebunch Wheatgrass

General Description

Bluebunch wheatgrass is a native, perennial, cool season bunchgrass with fibrous roots, sometimes forming clumps as wide as 150 cm (59 in). Stems range from 60 to 130 cm (24 to 51 in) tall, with narrow leaves mostly originating from the stem. Bluebunch wheatgrass reproduces primarily through seed but may reproduce vegetatively with short rhizomes on wetter sites. Bluebunch wheatgrass is an important species in British Columbia grasslands, occurring mostly in the south, central, and southeast parts of the province. It has historical importance in the development of the livestock industry in British Columbia because of its value for fall and winter grazing. It is also an important indicator of good ecological condition. 

Type

Native grass.

Origin

Bluebunch wheatgrass is native to British Columbia.

Longevity

Bluebunch wheatgrass is long lived.

Use

Reclamation, grazing. As an important native component in B.C. grasslands, bluebunch wheatgrass is an important species for consideration in reclamation and restoration. It provides valuable forage for wildlife and all types of livestock.

Optimal Time of Use

Bluebunch wheatgrass can support grazing in all seasons. Sufficient growth should be allowed before grazing bluebunch wheatgrass in the spring. At least 15 cm (6 in) of growth or allowing plants to reach the 4-leaf stage of development is recommended. Spring use should be deferred or alternated to fall use every 2–3 years. New stands should be well established (2–3 growing seasons) before grazing is allowed.

Recovery After Use

Repeated defoliation during the spring growth period is likely to reduce plant vigour, and lead to plant mortality (see McLean and Wikeem 1985). Suitable regrowth is likely to occur with late summer or fall rain if proper utilization (40–50% of growth) is applied in the spring season.

Palatability/Nutritional Value

Bluebunch wheatgrass is highly palatable to livestock and wildlife and provides good winter forage when rested during the growing season. Plants remain green well into summer. Crude protein of green leaf material sampled in May was 15%, and cured material sampled in November was 3% in the Kamloops area (McLean and Bawtree 1982).

Annual Precipitation min/max (mm)

200mm / 500mm

Drought Tolerance

Bluebunch wheatgrass is very drought tolerant.

Flooding Tolerance

Bluebunch wheatgrass is not tolerant of high water tables, saturated soils, or flooding.

Winter Hardiness

Bluebunch wheatgrass does best on medium-coarse textured soils, but also can be found on heavy- to medium- to coarse-textured soils.

Soil Texture Preference

Bluebunch wheatgrass does best on medium-coarse textured soils, but also can be found on heavy- to medium- to coarse-textured soils.

Erosion Control

Bluebunch wheatgrass can provide some erosion control on dry, disturbed sites where native vegetation is desired, but is not noted for erosion control.

Salinity Tolerance

Low tolerance. Bluebunch wheatgrass will tolerate weakly saline conditions.

Acidity Tolerance

Low tolerance. Bluebunch wheatgrass does not grow on moderate to highly acidic sites.

Alkalinity Tolerance

Not reported.

Seeds per kg

331,000 seeds/kg (150,139 seeds/lb)

Suggested Mixtures

Bluebunch wheatgrass should be seeded with other suitable native species, rather than with more competitive introduced species.

Ease of Establishment

Bluebunch wheatgrass is more difficult to establish than other native wheatgrasses. Seedbed preparation followed by drill seeding at depths of 0.6 to 1.27 cm (1/4 to 1/2 in.) produce the best results, but this method is likely to be unsuited to most projects and site conditions found in British Columbia. Broadcast seeding is likely to be more applicable, but establishment may be slow, and results mixed. Some B.C. restoration practitioners have used vegetative or plug plantings. Hay seeding using locally sourced plant materials was applied with marginal results on a restoration project in the South Okanagan.

Competitiveness

Bluebunch wheatgrass is reasonably competitive when it is well established in naturally occurring native plant communities.

Management Considerations

Bluebunch wheatgrass does not tolerate heavy, continuous grazing. A rest or deferred rotation grazing system is recommended to keep this grass in a healthy and vigorous condition.