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Pinaceae (Pinus)



Pinus (strobus)


Pinaceae

Pine Family


Pinus

strobus



L.










eastern white pine

PINSTR

Shenandoah National Park

P. strobus is found from Newfoundland to Manitoba, south to Delaware, Georgia, Kentucky and Iowa. It grows in fertile, well-drained, sandy soil.


plants

seed

Container (plug)

2+1 Gallon containers

3 Years

Stock Type: 2+1 seedlings in 1-gallon containers.
Height: 12" for 2+1 plants in gallon pots.
Time to grow: 2 years from seed in outdoor nursery beds; container plants were grown to 1 gallon size an additional year in the container nursery.

Root System: Container plants have full root systems that fill the pots. The insides of containers are treated with a copper hydroxide product to encourage development of a fibrous root system and prevent root girdling in the pot.


Fallen cones were collected on 9/12/96 in Shenandoah National Park.

Cleaning: After collection, cones are air-dried for days in cloth collection bags, which are laid out in full sun on greenhouse benches. Cones are shaken when open to release seeds and seeds are dewinged by hand rubbing.
Storage: seeds were planted after drying and were not stored.
Purity: estimated at 99% after cleaning.
Germination: untested; 10% of seeds planted in 1996 survived to harvest in 1998.
Seeds per Kg: 55,200

P. strobus needs 60 days cold stratification (USDA, 1974). Seeds are hand-sown in the fall in outdoor nursery beds to allow natural stratification to occur.

Propagation environment: Bareroot seedlings are grown to 2+0 in outdoor woody nursery beds. Selected 2 year old seedlings are transplanted to 1-gallon containers and grown an additional year in the container nursery as specimens.
Sowing date: seed was sown in outdoor nursery beds in early November.
Sowing/planting technique: Seeds are dusted with fungicide and hand-sown closely together into rows. Rows are 5 to 6 inches apart.Ectomycorrhizae are sprinkled over the seed before covering with about 0.75" of soil. The beds are then mulched with aged sawdust, which isscraped back in the spring before seedling emergence.


Seedlings emerge in the spring following a fall sowing. Emergence was not tracked, however of the 1,121 seeds sown, 110 seedlings were harvested.
New seedlings are monitored closely for irrigation needs and are shaded as soon as they emerge with poly screening at 30%. Shade cloth remains over seedlings until mid-August.


Container nursery: Selected bareroot seedlings were potted after harvest in one gallon containers that had been treated with copper hydroxide to prevent root girdling. Plants are grown in woody mix (3.8 cu ft. bale Sunshine #1, 4 cu. ft. of pine bark mulch, 20 oz. Nutricote and approximately 20 oz. ecto-mycorrhizae). Media is replenished yearly through bumpups or repotting. Container plants have been difficult to maintain in the container nursery under overhead irrigation.



During mid- to late summer, fertilization in the nursery beds is cut back to twice monthly. Beginning in September, irrigation is only used in a severe droughty situation. In the container nursery, irrigation is gradually reduced as weather cools.


Container seedlings have been overwintered under microfoam and in a cooler. Mildew and desiccation have been a problem.




Gleason, H and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States and Adjacent Canada. 2nd edition. New York Bot. Garden. USDA, Forest Service. 1974. Seeds of Woody Plants in the United States. USDA, Ag. Handbook 450. USDA NRCS National Plant Materials Center. Woody bed and container plant records. Unpublished.

Davis, Kathy; King, Brandy; Kujawski, Jennifer. 2003. Propagation protocol for production of Container (plug) Pinus strobus L. plants 2+1 Gallon containers; USDA NRCS - Norman A. Berg National Plant Materials Center Beltsville, Maryland. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2024/05/17). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.