Idaho Plant Materials Technical Note No. 24

fully tested and their full range of adaptation is not known at this time. Toe Jam is best adapted to loam to sandy loam
soils in the Great Basin and lower to middle Snake River Plains receiving 8-14 inches of annual precipitation. Fish
Creek is best adapted to sandy loam to silt loam to clay loam soils receiving 10 inches or more annual precipitation in
the middle to upper Snake River Plains. Additional bottlebrush squirreltail accessions are currently under evaluation by
ARS in Logan, NRCS at Bridger and Meeker PMCs and the Forest Service in Provo, Utah. Average seeds/ft 2 at 1 lb.
rate is 5. Seeding rate is 6 lb/ac.
Switchgrass
Panicum virgatum
Switchgrass is a perennial, tall, weakly sod-forming grass native to the Midwest and the Great Plains. It grows on a
wide range of soil textures and is tolerant of wet acid soils and brackish marshes. It provides excellent wildlife cover,
and seed is utilized as food by songbirds and game birds. It provides excellent late summer forage for livestock. It is
being used for biofuel applications in the Midwest. There may be a small niche for this species in the corn producing
areas of the Intermountain West under irrigation as a mid summer forage. It will not exceed forage production of other
irrigated forage varieties including orchardgrass and meadow brome. The best-performing winter hardy cultivar tested
in Idaho, Nevada and Utah is 'Blackwell'. Other releases include 'Dakotah', 'Forestburg' and 'Sunburst'. Average
seeds/ft 2 at 1 pound rate is 10. Seeding rate is 4 lb/ac.
Timothy
Phleum pratensis
An introduced bunchgrass adapted to cool, humid areas. It performs well, with moderate to high yields, on wet fertile
pasturelands; establishes cover quickly, volunteers readily on preferred sites, is late maturing, and is very palatable
early in the growing season (jointing stage) and only moderately palatable later in the growing season (post seed head
development). It should be grazed before the jointing stage and hayed before seed heads have emerged from boot.
Timothy hay is a premium feed for horses and is compatible in legume mixes. Severe damage can result from early
grazing during moist conditions. Regrowth is very slow following grazing or haying. It is adapted to high elevations
and areas where effective annual precipitation is 18 inches or irrigated. Recommended sites include cool, moist
meadows, ponderosa pine zone and above. It can also be used for ground cover and erosion control on cut or burnedover
timberland. Planting depth is 1/8 to 1/2 inch. Adapted varieties are ‘Aurora’, 'Climax', and 'Mohawk'. The
average seeds/ft 2 at 1 lb. rate is 28. Recommend pure stand seeding rate is 3 lb/ac.
Wheatgrass, Beardless Pseudoroegneria spicata inermis or Agropyron inerme
Beardless wheatgrass is a long-lived, drought tolerant, erect native bunchgrass. It differs from bluebunch wheatgrass in
the absence of awns. It begins growth in early spring and readily greens up in fall following fall rains. It is very
palatable, quality persists longer into growing season and forage yields are equal to crested wheatgrass. Recommended
sites include the 12-18 inch annual precipitation areas in mountain foothills after timber harvest or wildfire. It is best
adapted to winter-wet and summer dry climates. It has poor seedling vigor. Planting depth 1/4 to 1/2 inch. Adapted
variety is 'Whitmar'. Average seeds/ft 2 at 1 lb. rate is 3. The recommended pure stand seeding rate is 8.0 lb/ac.
Wheatgrass, Bluebunch Pseudoroegneria spicata or Agropyron spicatum
Bluebunch wheatgrass is a long-lived, drought-tolerant, widespread native bunchgrass. It begins growth early in spring
and again with the onset of fall rains. It is highly palatable and recovers rapidly after grazing but has low resistance to
repeated or heavy grazing. It is not recommended as a hay crop. Several years are required for stand to obtain full
productivity due to poor seedling vigor. Allow seedings to reach maturity (seedhead development) before grazing.
Recommended sites include foothills and valleys with 10-20 inches annual precipitation, sagebrush, ponderosa pine,
mountain brush and juniper-pinyon ranges. Low plant vigor results in poor stands on sites above 6500-ft. elevation.
Planting depth is 1/4 to 1/2 inch. Adapted varieties are Anatone Selected class germplasm for use above 10 inches of
precipitation and 'Goldar' and 'P7' for use above 12 inches of precipitation. 'Secar' (See Snake River Wheatgrass),
previously considered to be bluebunch wheatgrass but found to be a subspecies of thickspike wheatgrass, is more
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