Introduction
Propagate aspen from small root or stem cuttings started in 1.5" x 8" cone-tainers and transplanted into a nursery to grow to 3' tall 1-0 stock. Control growth via timing the planting in July, shade cloth and pruning the stem one or two times during the growing season. The ideal finished tree should be a 2' to 3' 1-0 stock that has well developed roots and is multi-stemmed to protect against browsing and buck rubs. Note, this is a new process that has yet to undergo Proof Of Concept (POC) testing. This document will be updated after POC testing.
Materials and Methods
Start ~2" rootlings or 4" dormant cuttings in July in 1.5" x 8" cone-tainers and flow trays under LED indoor growing lights. Grow until the shoots are about 3" tall then cut back to 2" to produce multi-stem plants. Acclimate outdoors for several days under a shade tree or shade cloth.
Push the cone-tainers into about 3"-4"into a raised tilled soil bed perhaps spaced 1" apart in 4 cone row blocks. Need to determine the optimal spacing to allow tree growth without allowing room for weeds. Perhaps apply a layer of pure washed sand between the cones.
Irrigate as needed and apply a foliar 20-20-20 water soluable fertilizer for optimal plant health, stress reduction without making them grow too fast and not harden properly (find the balance). If needed, cut back the main stem at some point to produce multiple stems and curtail growth. Remove the shade cloth some time in late-July, early August.
Ideally, lift the cone-tainers in the late Fall with roots attached after the leaves have fallen off and heal them in an angled lay down position, perhaps insulated by leaves/hay. I am concerned about water/ice filling the tubes and damaging plants and the tubes.
Lift the sets in the early Spring (March/April) cut of any external roots and store for re-propagation in July. Push out the roots from the top tube, cut the stem down to 7" and place the entire 12" tree in a bag and refrigerate until Spring field planting/shipping.
Ramp up numbers by using 2.25" root cuttings from the tube sections and potentially any stem cuttings.
Other options:
Open4st Generic Rootling Ramp-up Guidelines
1st-growing season: Grow donor ortet in pot within a pot in the ground in a an unheated green house or hoop house environment where the roots don't freeze so solid, and pot can be easily removed in February. Perhaps put a deep layer of leaves over the pot to protect it from freezing solid.
1st-dormant season: Make a 100 root segment ramet cuttings (5-cm long and 2 to 5 mm in diameter) in Feb/Mar and stick in cone-tainers or styroblocks to nurse along for 2 to 3 months. Try to propagate with low budget hoop house conditions.
2nd-growing season: Transplant the conetainer rootling materials into an outdoor nursery stool bed. Reserve a enough rootlings to grow in ortet pots for another generation of donor plants. Rinse and repeat the process...