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Pinaceae (Pinus)



Pinus (contorta)


Pinaceae

Pine family


Pinus

contorta

Variety

latifolia

Dougl.ex Loud.

Engelm. ex S. Wats.









Lodgepole pine

PINCON

Lodgepole forest, Many Glacier, Glacier National Park, Glacier Co., MT, 1585m elevation.

P. contorta var. latifolia is found in montane dry to moist areas, often forming pure stands;from southern Alaska and Yukon, southward to northern Baja California, east to Alberta and extreme southwestern Saskatchewan, South Dakota, and through the Rocky Mountains to Colorado. It is also common throughout the northeastern Oregon, Idaho, northern Utah, and extreme western Nevada.


plants

seed

Container (plug)

172 ml conetainers

9 Months

Stock Type: Container seedling.
Height: 16 cm.
Caliper: n/a.
Root System: firm plug in conetainer.

Serotinous and non serotinous cones are collected in early September. Mature seeds are firm and brown in color.
Cones are collected by cutting branches with pruning poles. Cones are removed from branches with pruning shears and stored in burlap bags in a well ventilated drying shed.

Serotinous cones are heated in kilns or placed in boiling water and then air dried to facilitate opening and seed extraction. A tumbler and dewinger are used to clean large quantities.
Seed longevity: is up to 25 years at 1 to 3C in sealed containers.
Seed dormancy is classified as physiological dormancy.
Seeds/Kg: 208,000 /kg
% Purity: 100%
% Germination: 80 to 94%

Seeds are treated with 8:1(v:v)water/bleach bath for 10 minutes, followed by a 48 hour running water rinse soak and a 45 day cold, moist stratification. Seeds are placed in fine mesh bags in moist peat moss and buried in ventilated containers at 3C. Nonstratified P. contorta seeds are reported to germinate to higher percentages in light than in darkness. Stratified seeds germinate to higher percentages in darkness. Prechilling may promote overall germination energy and uniformity.

Greenhouse and outdoor nursery growing facility.
Sowing Method: Direct Seeding. Stratified seeds are lightly covered with medium.
Growing medium used is 6:1:1 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.
Greenhouse temperatures are maintained at 21 to 25C during the day and 16 to 18C at night. Seedlings are hand watered and remain in greenhouse until mid May. Seedlings are then moved to outdoor nursery for the remainder of the growing season.

Medium is kept slightly moist during germination. Seeds must not be sown or covered too deeply. Initial germination is typically complete in 20 days. Germinants shed the seed coats 14 days after emergence. Seedlings are thinned at the birdcage stage.
Accelerated growth is usually reached by week 8.

8 weeks

Plants were fertilized with 25-10-10 liquid NPK at 200 ppm during the growing season. Seedlings can be inoculated with mycorrhizal fungi at this stage. Plants were fully root tight 23 weeks after germination and averaged 16 cm in height.

16 weeks

Tree seedlings are fertilized with 10-20-20 liquid NPK at 200 ppm in August and September. Irrigation is gradually reduced in September and October. Seedlings are flushed with clear water once before winterization.

4 weeks

Total Time To Harvest: 9 months
Harvest Date: September and October
Storage Conditions: Overwinter in outdoor nursery under insulating foam cover and snow.

5 months


One gallon container stock can be produced in 2 years with an average height of 37 cm and 1 cm caliper.
There are 2 botanical varieties; var. contorta, which is the coastal variety, and var. latifolia.

Flora of the Pacific Northwest, Hitchcock and Cronquist, 7th edition, University of Washington Press, 1973.

Seeds: Ecology, Biogeography, and Evolution of Dormancy and Germination, Baskin and Baskin, Academic Press, 1998.

Seeds of Woody Plants in North America, Young and Young, Dioscorides Press, 1992.

Glacier National Park Native Plant Nursery Propagation Records, unpublished.


Luna, Tara; Evans, Jeff; Wick, Dale; Hosokawa, Joy. 2008. Propagation protocol for production of Container (plug) Pinus contorta Dougl.ex Loud. plants 172 ml conetainers; USDI NPS - Glacier National Park West Glacier, Montana. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2024/12/22). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.