Stipa (occidentalis)

Mark E. Majerus USDA NRCS - Bridger Plant Materials Center 99 South River Road, Rte. 2, Box 1189 Bridger, Montana 59014-9718 (406) 662-3579 (406) 662-3428 (fax) mmajerus@mt.nrcs.usda.gov http://plant-materials.nrcs.usda.gov/mtpmc

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Family Scientific Name:	Poaceae
Family Common Name:	Grass
Scientific Name:	Stipa occidentalis
Common Name:	Western needlegrass
Species Code:	STOC2
Ecotype:	See
General Distribution:	Plains, rocky hills, and open woods; Wyoming to Washington, Arizona, and California.
Propagation Goal:	seeds
Propagation Method:	seed
ProductType:	Propagules (seeds, cuttings, poles, etc.)
Time To Grow:	0
Target Specifications:	Harvest yields vary due to weather and age of stand. Average annual production is 10 kg/ha (9 lbs/ac).
Propagule Collection:	Wildland collection occurs late July to early September when caryopsis are medium brown, at the hard dough stage, and not yet shattering (natural dispersal) from the open panicle; difficult to hand-harvest. One collection hour/person will yield an average 43 grams (1.5 oz) clean seed (ranges 15 to 66 grams and varies by year, stand density, and collector experience).
Propagule Processing:	Seed Processing: Seed is spread out on a tarp in a dry, sheltered environment and turned daily for approximately 3-5 days, until no moisture or warmth is detected. Seed is threshed with a hammermill through a 8/64" round hole screen; this process is repeated until awns are significantly reduced or completely removed. A Clipper M2B or Eclipse air-screen cleaner with a 7/64" round hole screen is used to process the threshed material. Due to the extremely persistent awns and reduced seed flow, this species is difficult to clean. Larger seed lots are processed most efficiently with mechanized cleaning equipment and smaller seed lots usually require more hand labor. Seeds/Kg: 580,534. Purtiy: 100%.
Pre-Planting Treatments:	Seed Treatments: None required.
Growing Area Preparation/ Annual Practices for Perennial Crops:	Propagation Environment: Seedbed is firm and free of weeds with good field moisture to 4" depth. Seed Propagation Method: Direct seeding.
Establishment Phase:	Sowing Date: Spring or dormant fall. Sowing/Planting Technique: 25-30 pure live seed/ft. (0.3 m) row, irrigated 91 cm (36 in) row spacing, seeded with 2-row double-disk planter with depth bands, optimum seeding depth 0.6 cm (0.25 in). Establishment Phase: Soil surface is kept moist throughout the 14 day germination and emergence period (also helps prevent soil crusting); lower rates of Buctrylr or bromoxynil are applied at 3-5 leaf stage to control broadleaf weeds. Fertilizer application is not recommended the first year, as it generally stimulates weed growth and competition.
Length of Establishment Phase:	2 growing seasons.
Active Growth Phase:	Rapid Growth Phase: Spring to fall; broadleaf weed control with herbicides must occur prior to boot stage; soil moisture is critical during boot stage, milk stage of seed development, and post harvest to pre-freezeup - no irrigation is applied during flowering (pollination); fertilizer is broadcast at 100 lbs actual N/40 lbs actual P/acre in mid-September.
Length of Active Growth Phase:	2 to 3 growing seasons.
Hardening Phase:	N/A.
Harvesting, Storage and Shipping:	Harvest Date: Cultivated harvest occurs early to late July, with a mean harvest date of July 14 at the Bridger Plant Materials Center. A John Deer swather is used to cut stems into windrows for direct combining, or, to minimize seed loss, a temporary "diaper" - a heavy piece of plastic or canvas clipped under belt draper - is attached for direct catchment. Seed Storage: Seed is placed in plastic seed bags and stored in a cool, dry environment. Seed Dormancy: Classified as physiological dormancy.
Length of Storage:	<b>Storage Duration:</b> 7-10 years.
Other Comments:	Ecotype: 1 Yellowstone National Park accession periodically collected and produced from 1988 to 1991. Ecological zone is subalpine fir forest. Elevation is 2,461 m (8,074 ft).
References:	Manual of the Grasses of the United States, A.S. Hitchcock, Second Edition, Two Volumes, Dover Publications, Inc., 1970. Flora of the Pacific Northwest, C. L. Hitchcock and A. Cronquist, University of Washington Press, 1973. Montana Interagency Plant Materials Handbook, Montana State University, Extension Service Bulletin EB 69, June 1990. Yellowstone Vegetation - Consequences of Environment and History in a Natural Setting, Don G. Despain, Roberts Rinehart Publishers, 1990. Seeds: Ecology, Biogeography, and Evolution of Dormancy and Germination, C. C. Baskin and J. M. Baskin, Academic Press, 2001.

Citation:

Winslow, Susan R.. 2002. Propagation protocol for production of Propagules (seeds, cuttings, poles, etc.) Stipa occidentalis seeds USDA NRCS - Bridger Plant Materials Center Bridger, Montana. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2024/05/04). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.