Pyrrocoma (liatriformis)

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

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Family Scientific Name:	Asteraceae
Family Common Name:	Sunflower
Scientific Name:	Pyrrocoma liatriformis Greene
Common Synonym:	Haplopappus liatriformis (Greene) St. John
Common Name:	Palouse goldenweed
Species Code:	PYLI
Ecotype:	Paradise Creek drainage near Pullman, WA.
General Distribution:	Restricted to grasslands of the Palouse Prairie of southeastern Washington and adjacent northern Idaho. Ranked G2 globally and S2 in both Washington and Idaho and considered a "species of concern" under the Endangered Species Act.
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. It ripens in September. It is collected when the pappus begins to expand. Seed is tan to grey in color and wind disseminated, so must be collected before it blows away. Seed maturity is indeterminant. Seed can be collected using a vacuum. This removes only mature seed, leaving immature seed to ripen, and reduces the amount of trash which subsequently must be cleaned from the seed. Harvested seed is stored in paper bags at room temperature until cleaned. We determined 357 seeds/gram or 161,740 seeds/lb for this ecotype.
Propagule Processing:	Small amounts are rubbed to free the seed, then cleaned with an air column separator. Larger amounts are threshed with a hammermill, then cleaned with air screen equipment. Clean seed is stored in controlled conditions at 40 degrees Fahrenheit and 40% relative humidity.Sterile rice hulls can be added to the hammermill to facilitate removal of the pappus. This is not necessary if there are stems and leaves collected with the seed.
Pre-Planting Treatments:	Seed germinates readily without pretreatment. Unpublished data from trials conducted at the Pullman Plant Materials Center comparing untreated seed with seed treated by cold moist stratification for periods of 30, 45, or 90 days showed no increase in total emergence following stratification, although stratified seed may emerge 1-2 days sooner. The slight delay with untreated seed is probably due to the time required for the seeds to imbibe water and initiate the germination process.
Growing Area Preparation/ Annual Practices for Perennial Crops:	In January seed is sown in the greenhouse in 10 cu. in. Ray Leach Super cell conetainers filled with Sunshine #4 and covered lightly. Head space of ¬ to « inch is maintained in conetainers to allow deep watering. 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.
Establishment Phase:	Medium is kept moist until germination occurs. Germination usually begins in 6 days and is complete in 18-20 days.
Length of Establishment Phase:	3 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.
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:	Achenes are sometimes attacked by insect larva. Crown rot can affect the plant and the woody caudex is eaten by rodents.
References:	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. 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, 8 February 2007). National Plant Data Center, Baton Rouge, LA 70874-4490 USA.

Citation:

Skinner, David M,. 2007. Propagation protocol for production of Container (plug) Pyrrocoma liatriformis Greene plants 10 cu. in.; USDA NRCS - Pullman Plant Materials Center Pullman, Washington. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2025/04/20). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.