Penstemon (acuminatus)

Ann DeBolt and Hilary Parkinson USDA FS - Rocky Mountain Research Station 316 E. Myrtle Boise, Idaho 83702 208-373-4366 208-373-4391 (fax) adebolt@fs.fed.us www.fs.fed.us/rm/boise

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Family Scientific Name:	Scrophulariaceae
Family Common Name:	Figwort family
Scientific Name:	Penstemon acuminatus Dougl.
Common Name:	Sand penstemon, Sand-dune penstemon, Sharp-leaved penstemon
Ecotype:	Mountain Home Uplands (associated with basin big sagebrush, Indian ricegrass, bitterbrush), Elmore County, ID, 817 m
General Distribution:	On sandy soils of dunes and other dry places at low elevations; east of the Cascade Mountains in Washington, Oregon, northern Nevada and western Idaho (to Gooding County).
Propagation Goal:	plants
Propagation Method:	seed
ProductType:	Container (plug)
Time To Grow:	0
Propagule Collection:	Pale blue to purple flowers bloom from April to May. Phenology varies based on elevation, aspect and seasonal weather patterns. The fruit (a capsule) is mature when it turns brown and begins to open, which typically occurs 5 to 8 weeks after flowering. Fruit maturation is quite uniform. Capsules do not retain seed for more than a couple of weeks beyond maturation. Seeds were collected by cutting mature inflorescences (racemes) with clippers and placing them in containers. After collection, the capsules were thoroughly dried and placed in a standard freezer for 48 hours to remove insect pests. Seed was stored in a brown glass bottle at room temperature for 18 months prior to propagation trials. Seeds are a dull brown color, 2 mm in size, and number 400,000-500,000 per pound.
Propagule Processing:	Capsules are crushed on a rubbing board and then screened through sieves with 2 mm and 1 mm square openings (Nos. 10 and 18 USA STS) to remove debris. Debris is removed by passing the material through a seed blower twice, followed by screening through a sieve with 1.7 mm square openings (no. 12 USA STS). Tetrazolium tests (Idaho State Seed Laboratory) determined that viability was 89% and purity 96% (85.4% PLS). Fifty-three percent of the viable seeds germinated. Germination of prechilled seeds began after 3 days of incubation and was 70% complete by the fourth day. Seeds continued to germinate sporadically for 48 days.
Pre-Planting Treatments:	Seed was soaked in 250 ppm giberellic acid for approximately 24 hours and then placed in germination boxes on two layers of blotter paper moistened with distilled water. Additional water was added as needed. Seed was prechilled at 4§C in the dark for 60 days. Mold began to form in the germination boxes after 30 days. The blotter paper was replaced and seeds were washed with Thiram, an anti-fungal seed protectant. After the 60 days of prechilling, seeds were incubated in a germinator at a constant 21§C with exposure to 12 hours of cool-white fluorescent light alternating with 12 hours of darkness.
Growing Area Preparation/ Annual Practices for Perennial Crops:	Upon first signs of germination, seeds were sown in styrofoam conetainers filled with a mixture of 50% peat and 50% vermiculite. Containers were watered from an automatic overhead irrigation system which turns on when soil saturation levels fall below 80% and turns off when soil reaches 100% field capacity. Greenhouse temperature is set to a constant 27§C. Small amounts of fertilizer suitable for seedlings were added periodically.
Establishment Phase:	Only 19% of the germinants survived in the greenhouse. A longer prechill may have increased germination. Adding a thin layer of sand or gravel in each cell might permit more rapid surface drying and reduce the incidence of damping off.
Other Comments:	Acknowledgements: Partial funding for this research was provided by the USDI Bureau of Land Management, Great Basin Restoration Initiative. The use of trade or firm names in this publication is for reader information and does not imply endorsement by the U.S. Department ofAgriculture of any product or service. This publication reports research involving pesticides. It does not contain recommendations for their use, nor does it imply the uses discussed here have been registered. All uses of pesticides must be registered by appropriate State and/or Federal agencies before they can be recommended. CAUTION: Pesticides can be injurious to humans, domestic animals, desirable plants, and fish or other wildlife-if they are not handled or applied properly. Use all pesticides selectively and carefully. Follow recommended practices for the disposal of surplus pesticides and pesticide containers.
References:	Hitchcock, C. Leo, and Arthur Cronquist. 1973. Flora of the Pacific Northwest. University of Washington Press, Seattle, WA. 730 p. USDA, NRCS. 2004. The PLANTS Database, Version 3.5 (http://plants.usda.gov). National Plant Data Center, Baton Rouge, LA 70874-4490 USA.

Citation:

Parkinson, Hilary; DeBolt, Ann. 2005. Propagation protocol for production of Container (plug) Penstemon acuminatus Dougl. plants USDA FS - Rocky Mountain Research Station Boise, Idaho. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2024/07/02). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.