Helianthella (uniflora)

Dave Skinner PMC Farm Manager USDA NRCS - Pullman Plant Materials Center Room 211A Hulbert Hall WSU Pullman, Washington 99164-6211 509-335-9689 509-335-2940 (fax) abbie@wsu.edu http://plant-materials.nrcs.usda.gov/wapmc

---

Family Scientific Name:	Asteraceae
Family Common Name:	Sunflower
Scientific Name:	Helianthella uniflora (Nutt.) Torr. & Gray douglasii (Torr. & Gray) W.A. Weber
Common Name:	false sunflower, Rocky Mountain helianthella, oneflower helianthella, Douglas' helianthella, little sunflower
Species Code:	HEUND
Ecotype:	Paradise Creek drainage near Pullman, Washington.
General Distribution:	Shrub-steppe to open pine forests east of the Cascade Mountains of southern British Columbia, Washington, Oregon, Idaho, and Montana. For the species, mean annual precipitation range is from 10-35 inches (USDA NRCS 2007).
Known Invasiveness:	not invasive
Propagation Goal:	plants
Propagation Method:	seed
ProductType:	Container (plug)
Stock Type:	10 cu. in.
Time To Grow:	4 Months
Target Specifications:	Tight root plug in container.
Propagule Collection:	Fruit is an achene which ripens from mid July to mid August. Seed is dark grayish-brown to nearly black in color. The pappus is reduced to two unequal awns and the achene is not windborne. Seed will hold in the inflorescence longer than the seed of many other members of Asteraceae, but will shatter within a week or so of ripening. Flowering and seed maturity are indeterminant and seed should be collected every 3-4 days to maximize volume. Seed is easily collected by stripping it from the infloresecence by hand. It is stored in paper bags at room temperature until cleaned.
Propagule Processing:	Small amounts are rubbed to free the seed, then cleaned with an air column separator. Larger amounts are threshed with a belt thresher, then cleaned with air screen equipment. Clean seed is stored in controlled conditions at 40 degrees Fahrenheit and 40% relative humidity. 52,500-72,300 seeds/lb for the species (Hassell et al 1996). We determined 41,087 seeds/lb or 91 seeds/gram for this ecotype (USDA NRCS Pullman Plant Materials Center 2005).
Pre-Planting Treatments:	While some seed will germinate without pretreatment, for this ecotype 45 days of cold moist stratification results in the highest germination. Link (1993) reports that pretreatment is not needed. The Association of Official Seed Analysts suggests that laboratory germination be carried out at 15oC with alternating light or at alternating 20-30oC in the dark (Chirco & Turnoer 1986). However, they based that suggestion on work by Maguire and Overland (1959) which resulted in only 8% germination for either treatment. While that was the highest germination Maguire and Overland achieved for any combination of temperature and light, they did not try stratifying the seed beforehand. Working with seed collected from the Palouse Prairie of eastern Washington and northern Idaho, Nauman (2002) found that seed germinated best with 120 days of cold moist stratification and exposure to light. Unpublished data from trials conducted at the Pullman Plant Materials Center revealed that 45% emergence occurred without stratification. 45 days of cold, moist stratification resulted in 80% emergence. 90 days of cold, moist stratification resulted in 60% emergence. Seed sown in containers in November and left outdoors under cool, fluctuating spring temperatures began emerging in mid-March but only reached 2.5% emergence. Untreated seed required 10-12 days to emerge while seed stratified for 45 days began emerging in 5 days and seed stratified for 90 days began emerging within 1 day of the end of the stratification period. Since it was sown covered, we were unable to observe the seed, but this suggests that seed is able to begin the germination process under cool temperatures. Work by Nauman (2002) confirms that seed of this species is able to germinate at low temperatures. This could have contributed to the extremely low emergence for the seed left outside to germinate in cool early spring conditions. Those seeds were subjected to a cold period of several days duration in late February when night temperatures dropped to near 0oF after all the other treatments had been moved into the greenhouse. It is surmised that the extreme cold killed the seeds after they had begun to germinate but before they emerged. Due to the large seed size and the difficulty of keeping surface sown seed hydrated in a greenhouse, we did not investigate the effects of light on germination. Other work conducted by the Pullman Plant Materials Center outside this particular trial indicates that 30 days of cold moist stratification is not sufficient to increase germination above that of untreated seed.
Growing Area Preparation/ Annual Practices for Perennial Crops:	In late November or early December seed is sown in 10 cu. in. Ray Leach Super cell conetainers filled with Sunshine #4 and covered lightly. A thin layer of coarse grit is applied to the top of the planting soil to prevent seeds from floating during watering. Conetainers are watered deeply and placed outside. Alternately, seed can be moist stratified in a refrigerator for 45 days before sowing in the greenhouse.
Establishment Phase:	Containers are moved to the greenhouse in January. Emergence usually begins in 5 days and is complete in 12 days. Unstratified seed will take 10-23 days to emerge and total emergence will be lower. Seed stratified for longer periods will emerge sooner, but total emergence is not increased. A few seeds will emerge as much as 3-4 weeks after being placed in the greenhouse under any pretreatment.
Length of Establishment Phase:	2 weeks
Active Growth Phase:	Plants are watered deeply every other day and fertilized once per week with a complete, water soluble fertilizer containing micro-nutrients. Plants may require water every day during the final part of the active growth period.
Length of Active Growth Phase:	3 months
Hardening Phase:	Plants are moved to the cold frame in late March or early April, depending on weather conditions. They are watered every other day if the weather is cool, and every day during hot, dry spells.
Length of Hardening Phase:	2-4 weeks
Other Comments:	Plants continue to produce good seed crops in increase plantings for at least 5 years. The larva of an unidentified insect feeds in the developing seed. Preliminary data from direct seeding trials in the field suggest that fall seedings are better than spring seedings, but none of the treatments has resulted in high or consistent success rates.
References:	Chirco, Ellen, and Terry Turnoer. 1986. Species without AOSA Testing Procedures. The Newsletter of the Association of Official Seed Analysts 60(2):2-66. Available online at http://www.aosaseed.com/Species%20wo%20AOSA%20list%20plus%20adds.pdf. Updated 11/10/03. Craighead, John J., Frank C. Craighead, and Ray J. Davis. 1963. A Field Guide to Rocky Mountain Wildflowers. Houghton Mifflin Co. Boston, MA. 277 pp. Hassell, Wendell, W. Rocky Beavers, Steve Ouellette, and Thomas Mitchell. 1996. Seeding Rate Statistics for Native and Introduced Species. USDI National Park Service and USDA Natural Resources Conservation Service. 25 pp. Hitchcock, C. Leo, and Arthur Cronquist. 1973. Flora of the Pacific Northwest. University of Washington Press. Seattle, WA. 730 pp. Larrison, Earl J., Grace W. Patrick, William H. Baker, and James A. Yaich. 1974. Washington Wildflowers. The Seattle Audubon Society. Seattle, WA. 376 pp. Link, Ellen (ed.). 1993. Native Plant Propagation Techniques for National Parks Interim Guide. USDA SCS Rose Lake Plant Materials Center and USDI National Park Service. East Lansing, Michigan. 240 pp. Lyons, C.P. 1997. Wildflowers of Washington. Lone Pine Publishing, Renton, WA. 192 pp. Maguire, James D. and Alvin Overland. 1959. Laboratory Germination of Seeds of Weedy and Native Plants. Washington State Agricultural Experiment Station Circular 349, Pullman, WA. 15 p. Nauman, C. 2002. Germination of 12 Palouse Prairie forbs after stratification under light and dark treatments. M.S. Thesis, University of Idaho. Piper, C.V., and R.K. Beattie. 1914. The Flora of Southeastern Washington and Adjacent Idaho. Lancaster, PA. Press of the New Era Printing Company. 296 p. Rickett, Harold W. 1973. Wildflowers of the United States: The Central Mountains and Plains. Vol. 6. (3 parts). McGraw Hill, New York. St. John, Harold. 1963. Flora of Southeastern Washington and of Adjacent Idaho. 3rd edition. Outdoor Pictures. Escondido, CA. 583 pp. USDA NRCS. 2007. The PLANTS Database (http://plants.usda.gov, 12 March 2007). National Plant Data Center, Baton Rouge, LA 70874-4490 USA. USDA NRCS Pullman Plant Materials Center. 2005. Seed Weights of Some Palouse Native Species. Pullman Plant Materials Center, Pullman, Washington. Online at http://www.wsu.edu/~pmc_nrcs/Docs/Seed_Weights_Palouse_Native_Species.pdf Visalli, Dana, Walt Lockwood, and Derrick Ditchburn. 2005. Northwest Dryland Wildflowers: Sagebrush-Ponderosa. Hancock House Publishers, Blaine, WA. 96 pp.

Citation:

Skinner, David M,. 2007. Propagation protocol for production of Container (plug) Helianthella uniflora (Nutt.) Torr. & Gray plants 10 cu. in.; USDA NRCS - Pullman Plant Materials Center Pullman, Washington. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2024/07/03). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.