This project examines growth responses of juvenile subalpine fir to variation in residual canopy cover, site quality and crowding. The study examines the relative strength of different factors affecting juvenile tree growth, including light, water, nutrient availability and neighbourhood crowding. The study was conducted in the Montane Spruce zone in the Southern Interior Forest Region. We sampled subalpine fir seedlings/saplings growing across a light gradient over a wide range of tree densities and site qualities. Sample trees were destructively sampled to measure growth increment, which was used to relate seedling growth to its growing environment. For each tree, we stem mapped the location of neighbourhood trees in a 3.99m radius plot, measure light availability, foliar nutrients, soil water availability, and water use efficiency. Our improved mechanistic understanding of juvenile growth will be linked to SORTIE-BC. SORTIE-BC is a resource-mediated, spatially explicit, mixed-species forest model that makes population dynamic forecasts for juvenile and adult trees. It has a flexible user-interface that allows the user to incorporate a wide range of silvicultural strategies (e.g. clearcutting, understory protection, understory planting, diameter limit harvesting, shelterwood, single or group selection, and variable retention). With the model, we can examine how complex stands respond to a wide range of silvicultural strategies, at different spatial scales and over different time periods, which is an impossible task for traditional field-based research. Our research approach can assist foresters and managers in testing, developing and choosing silvicultural strategies to achieve sustainable management objectives.
Forest Investment Account (FIA). 2006. Improving predictions of juvenile tree growth in complex mixtures for sustainable forest management. Forest Investment Account (FIA) - Forest Science Program. Forest Investment Account Report. FIA2006MR114