Master’s Thesis

Master’s Research Project

During my master’s research I examined the impacts of variable retention harvesting on residual tree mortality and natural regeneration of white spruce [Picea glauca (Moench (Voss)] in northern Alberta at the EMEND (Ecosystem Emulating Natural Distrubance)  site. The variable retention harvesting was done in four overstory canopy compositions (ranging from deciduous dominated to conifer dominated) and at six rates of canopy retention (2%, 10%, 20%, 50%, 75% and 100%). After 10 years there was 32.9 % mortality of aspen (Populus tremuloides Michx.) and 16.9 % mortality of spruce in the variable retention cuts. Mortality of individual trees was greater with low density of trees, in the conifer stands and for trees with short live crowns, which are large and trees near machine corridors. Natural regeneration of spruce was greatest with higher availability of seed trees (>30 ha-1) and on machine corridors, where stocking reached 74%. By contrast, stocking was ≤14% on retention strips, when seed tree density was ≤11 seed trees ha-1.

Residual Tree Transect
Residual Tree Transect
Spruce Seedling
White Spruce Seedling
Spruce Seedling Snow
Spruce Seedling in Snow


Curious about the entire project: Click the following link to view entire thesis:
Variable Retention Harvesting: Mortality of Residual Trees and Natural Regeneration of White Spruce