Populus (tremuloides)

Randy Moench Nursery Manager Colorado State Forest Service Nursery Foothills Campus, Bldg. 1060 Fort Collins, Colorado 80523 970-491-8429 970-491-8250 (fax) rmoench@lamar.colostate.edu http://www.colostate.edu/Depts/CSFS

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Family Scientific Name:	Salicaceae
Family Common Name:	Willow family
Scientific Name:	Populus tremuloides (Michx.)
Common Name:	Quaking aspen
Species Code:	POPTRE
Ecotype:	Larimer county, CO 7500-8000' elevation.
General Distribution:	P. tremuloides is found from Alaska to Labrador,south to California, northern Mexico, Tennessee and New Jersery.
Propagation Goal:	plants
Propagation Method:	seed
ProductType:	Container (plug)
Stock Type:	1+0 container
Time To Grow:	5 Months
Target Specifications:	Height: 12 in. Caliper: 4 mm. Root System: Firm plug.
Propagule Collection:	Source of Seeds: Self-collected. Collection Date: Start looking in mid to late May, but check frequently because seeds develop and blow away within a few weeks.
Propagule Processing:	Seeds/Kg: 3,000,000%. Germination: 90%+. % Purity: Contains leaf chaff. Seed Processing: Collect branches with mature yet closed catkins. Put branches in water-filled large garbage cans in a warm enclosed room with little air movement. Within 5 days catkins will open releasing cotton in a controlled fashion. Vacuum up cotton. Separate seeds from cotton in center sieve between two additional standard testing sieves (total of three), middle sieve sized to permit seed passage. Sieve sizes top to bottom: Gilson #18 (1.00 mm), #35 (500 micrometer), #140 (106 micrometer). Gently blowing air from a reversed shop-vac through the sieves removes the seed from the cotton. Seed collects in bottom sieve. Seed storage: Store at -7 § C (20 § F) in sealed glass vial to eliminate drying. % Germination: 90%+
Pre-Planting Treatments:	None, usually collected in spring of year one, seed is sown spring of year two.
Growing Area Preparation/ Annual Practices for Perennial Crops:	Propagation Environment: Shadehouse. Container Type and Volume: Colorado Styroblock - 492 cm3 (30 in3). Growing Media: Scotts Forestry Mix.
Establishment Phase:	Sowing Date: Late May. % Emergence and Date: Germination within 24 hours, cotyledons within 48 rs. Sowing/Planting Technique: Manual sowing with salt shaker. Establishment Phase: Light misting twice a day until germination. Germination to two true leaf stage takes two weeks and seedlings are thinned to one per container at that time. Regular deep watering twice a week with complete fertigation solution based on 100 ppm nitrogen.
Length of Establishment Phase:	3 weeks
Active Growth Phase:	Late June to mid-August. Continue twice a week fertigation. Apply VA mycorrhizae beginning of phase. We use a product called BuRize from Buckman Laboratories.
Length of Active Growth Phase:	6 weeks
Hardening Phase:	In mid-August cease fertilizing, flush with clear water, reduce waterings until leaf drop in early October.
Length of Hardening Phase:	6 weeks
Harvesting, Storage and Shipping:	Total Time to Harvest: Seedlings can be grown to specifications in five months, stored overwinter in the shadehouse, and ready to ship the following spring Harvest Date: Seedlings can be graded after leaf drop in early October or prior to shipping the following spring. Storage Conditions: Outdoor shadehouse.
Length of Storage:	5 months
References:	Seed collection guide available at:http://www.colostate.edu/Depts/CSFS/Aspenseed.pdf

Citation:

Moench, Randy. 2001. Propagation protocol for production of Container (plug) Populus tremuloides (Michx.) plants 1+0 container; Colorado State Forest Service Nursery Fort Collins, Colorado. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2025/02/24). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.