To Grass Species
|
To Grass Species |
|
Plant Species
From Montana
Interagency Plant Materials Handbook *
By S. Smoliak,
R.L. Ditterline, J.D. Scheetz, L.K. Holzworth, J.R. Sims, L.E. Wiesner, D.E.
Baldridge, and G.L. Tibke
Big bluegrass is a long-lived, native, perennial bunchgrass growing 2 to 4 feet high. It starts very early in the spring and reaches grazing readiness earlier than crested wheatgrass. It competes with winter annual weeds and, when properly managed, will crowd out cheatgrass. Plants have an abundant, deep root system as well as extensive shallow roots. Plants are dormant during the hot summer and recovery is good with cool weather and fall rains. Compared with other grasses, big bluegrass makes a higher percentage of its total growth before soil moisture is exhausted. Seed should be treated with an approved fungicide or seed protectant before planting to insure against seed decay. Big bluegrass has been successfully used for reseeding burned-over forest lands in pine zones of western states. Upland game birds, especially pheasants, choose fields of big bluegrass for nesting sites because the bluegrass has more early spring growth than any dryland grass and the basal leaves provide good shade.
Description
Big bluegrass is the largest of the native bluegrasses found in the intermountain zone of the northwest states. It is a tall, tufted grass that is remarkably drought resistant. It is leafy, with long, flat leaves that are typically bluegrass, boat-shaped at the tip. It grows erect and has numerous, find stems. Ligules are broad and flat. It heads early, has erect seed heads, and produces abundant seed. Seeds are small, nearly one million per pound. Seeds shatter readily and grow with the first fall rains. It is high in seed, forage and root production. It has moderately abundant leaves and a large compact seed head.
Adaptation
Big bluegrass is native to the Montana foothills and can be used for range seedings on adapted sites. It has remarkable root-producing ability, and is planted alone or in mixtures with crested wheatgrass in semi-arid areas. It also has proved satisfactory in dryland hay seedings with alfalfa. It grows well on a variety of soils at elevations up to 6,000 feet and over 12 inches of average annual precipitation. Native strains have been found up to 9,000 feet in elevation.
Where it is impossible to prepare a seedbed, such as burned-over forest areas, big bluegrass is well-adapted for broadcast seedings. Unused plantings will retain stands for many years through renewal from shattered seed. Establishment of big bluegrass requires special care. The seedling vigor is good for such a small-seeded grass, but seedlings become established only from shallow seedings made during the cool temperatures of late fall, winter or earlyspring. Seed no deeper than 1/2 inch.
Limitations
Seedlings of big bluegrass are reported to be subject to winter damage from frost heaving because of a weak root system. Overgrazing and severe trampling are injurious to native stands of this grass and without proper protective grazing, a range will deteriorate rapidly. The plants in new seedings are pulled up by grazing animals and, therefore, should not be grazed until the stands are more than two years old and are sufficiently well-rooted to stand grazing.
Use for Hay
Big bluegrass makes good nutritious hay that is at least as palatable as timothy and smooth bromegrass. It has also proved satisfactory in dryland hay seedings with alfalfa. Hay plantings should be cut immediately after full bloom of the grass or, if in mixtures, when alfalfa begins to bloom. Do not pasture hay plantings except for light aftermath grazing.
Use for Pasture
Early spring grazing by cattle or sheep is one of the primary uses of big bluegrass seedings. In adapted areas, there is no other grass that provides an equal volume of early spring forage. It makes good spring calving or lambing pasture. 'Sherman' big bluegrass also makes excellent standing forage for fall and winter grazing.
Cattle prefer big bluegrass in the spring and it should be grazed when growth reaches eight inches. Livestock graze big bluegrass in the vegetative stage, but avoid it when headed. Livestock should be removed while there is still enough moisture in the ground so some regrowth can be made before plants go dormant. Regrowth can be grazed after plants turn green in the fall, but a 6-inch stubble should be left. Allow big bluegrass to become well established before grazing (one or two full growing seasons).
Seed Production
Big bluegrass produces 300 to 400 pounds of seed per acre. Seed harvest dates are from June 29 to July 7 in south-central Montana. Seed shatters readily and should be cut with a binder or windrowed before combining. Seed is easily cleaned. 'Sherman' big bluegrass retains a viability of more than 70 percent for 14 years when stored under cool, dry conditions
* The Montana
Interagency Plant Materials Handbook (EB69)
is no longer in print, but is available for viewing in
Montana County Extension Service and National Resource Conservation Service
Offices.