Cirsium (hookerianum)

Tara Luna USDI NPS - Glacier National Park West Glacier, Montana 59936 (406) 888-7835 http://plant-materials.nrcs.usda.gov/azpmc

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Family Scientific Name:	Asteraceae
Family Common Name:	Sunflower family
Scientific Name:	Cirsium hookerianum Nutt.
Common Name:	White thistle
Species Code:	CIRHOO
Ecotype:	Subalpine slope, Haystack Butte, Glacier National Park, Flathead Co., MT..
General Distribution:	C. hookerianum occurs on open slopes east of the Cascades; B.C. and Alberta south to northern Wyoming, northern Idaho, and northwest Montana.
Propagation Goal:	plants
Propagation Method:	seed
ProductType:	Container (plug)
Stock Type:	3L (1 gallon) containers
Time To Grow:	9 Months
Target Specifications:	Height: 6 to 10 true leaves, 7 cm<br> Caliper: n/a<br> Root System: firm plug in conetainer in 172 ml conetainers.
Propagule Collection:	Collect mature achenes when in mid September when they turn grey and are easily separated from the receptacle. Seeds are collected in paper bags and kept in a well ventilated drying shed prior to cleaning.
Propagule Processing:	Seeds are hand cleaned at the nursery. Seed longevity is unknown. Seed dormancy is classified as physiological dormancy. Seeds/Kg:550,000/kg % Purity: 100% % Germination: 50%
Pre-Planting Treatments:	5 month outdoor cold, moist stratification.
Growing Area Preparation/ Annual Practices for Perennial Crops:	Outdoor nursery growing facility. Sowing Method: Direct seeding. Seeds are covered wth medium. Growing medium used is milled sphagnum peat,perlite, and vermiculite with Osmocote controlled release fertilizer (13N:13P2O5:13K2O; 8 to 9 month release rate at 21C) and Micromax fertilizer (12%S,0.1%B,0.5%Cu,12%Fe,2.5%Mn, 0.05%Mo,1%Zn) at the rate of 1 gram of Osmocote and 0.20 gram of Micromax per 172 ml conetainer. Conetainers are filled and sown in late fall and irrigated thoroughly prior to winter stratification.
Establishment Phase:	Medium is kept slightly moist during germination. Germination occurs when temperatures reach 22C or above during the day and is usually complete in 2 weeks. Seedlings are thinned at this stage. After seedlings are well established, they must dry down between irrigations.
Length of Establishment Phase:	4 weeks
Active Growth Phase:	Root development occurs rapidly following germination. Seedlings were uppotted into a well aerated medium media and were root tight in 3L (1 gallon) containers in 8 weeks. Plants were fertilized with 20-20-20 liquid NPK fertilizer at 100 ppm during the growing season.
Length of Active Growth Phase:	8 weeks
Hardening Phase:	Irrigation is gradually reduced in September and October. Plants are flushed with clear water and fertilized with 10-20-20 liquid NPK fertilizer at 200 ppm once before winterization.
Length of Hardening Phase:	4 weeks
Harvesting, Storage and Shipping:	Total Time To Harvest:9 months Harvest Date:September Storage Conditions: Overwinter in outdoor nursery under insulating foam cover and snow.
Length of Storage:	5 months
References:	Flora of the Pacific Northwest, Hitchcock and Cronquist, 7th edition, University of Washington Press, 1973. Seeding Rate Statistics for Native and Introduced Species, Hassell, Wendel, U.S.D.I. and U.S.D.A., April 1996. Seeds: Ecology, Biogeography, and Evolution of Dormancy and Germination, Baskin and Baskin, Academic Press, 1998. Seed Germination Theory and Practice, Deno, Norman, Penn State University, 1993. Glacier National Park Native Plant Nursery Propagation Records, unpublished.

Citation:

Luna, Tara. 2008. Propagation protocol for production of Container (plug) Cirsium hookerianum Nutt. plants 3L (1 gallon) containers; USDI NPS - Glacier National Park West Glacier, Montana. 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.