Yellow-Cedar Regeneration
Yellow-cedar often does not reproduce prolifically and may require measures to ensure that it successfully regenerates. Vegetation reproduction through layering (i.e., rooting of lower branches) occurs, but this phenomenon is mainly restricted to open bog sites where live lower limbs contact the ground. The degree to which seed tree harvests promote yellow-cedar regeneration is unknown in Alaska. A planting trial established in 1986 on Etolin Island of yellow-cedar seedlings demonstrated that the species can be regenerated on logged sites, as long as it is planted quickly after harvest. A subsequent study near Ketchikan showed that stecklings (rooted cuttings) could substitute for seedlings.
Research and development are needed on barriers related to the early establishment phase of regeneration (below). Once established by natural regeneration or planting, thinning can be used to favor yellow-cedar to maintain its competitive status with other conifers. Silvicultural experience with yellow-cedar is needed in the region to ensure that the species can be managed long-term to produce timber and other resource needs. A genetics program aimed at breeding for slow spring dehardening and freezing resistance could be employed to restore yellow-cedar in areas prone to the decline problem. Surviving yellow-cedar trees in patches of intensive decline could have experienced selective pressure favoring spring cold tolerance and would be good candidates for genetic testing.
Barriers to artificial regeneration through planting are mainly:
seed collection & germination | competing vegetation |
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deer browse | spring freezing injury |
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