Does Minnesota aspen have a delayed fall phenology in Alberta?
–- An exploratory assessment of aspen seed transfer to address climate change in western Canada

Chen (Klaus) DING, PhD student
Department of Renewable Resources
Phone: (780) 492- 2540, email: [email protected]

Quaking aspens (Populus tremuloides) from Minnesota grow faster than local populations in central Alberta based on provenance trials as a result of a lengthening growing season.  As their spring phenology such as bud break is not earlier than the local, their timing of fall phenology (e.g., bud set and leaf senescence) is later.  Late fall phenology makes them vulnerable to early winter frost and the timing of the phenological events is critical for survival and height growth of aspen populations.  The interaction between aspen fall phenology and environmental conditions (e.g., latitude, daylight length and climatic conditions) was studied with the timing of aspen fall phenology based on the provenance trials (2006) and remote sensing data (2001-2006) in western Canada and Minnesota are statistically with a reference of the climatic data.  Using remote sensing and GIS to monitor and analyze aspen adaptive variation is a novel approach.  Regression analyses and multivariate analyses such as cca, PCA and classification tree are applied. Bud set and leaf senescence are sensitive to photoperiod (daylight length) and climatic condition (e.g., temperature, frost free days).   The pilot results indicate a late bud set and brown-down trend of Minnesota aspen populations in Alberta, which presents  geographic clinal trend of aspen from northern British Columbia to Minnesota.  Bud set are more sensitive to daylight length, latitude and autumn temperature conditions while the brown-down event more relates to daylight length and latitude.  These results suggest that adjusting Minnesota aspen to places of a warming autumn could potentially decrease its early frost risks.  The remote sensing data of aspen brown-down from 2000 to 2006 shows the climatic condition affects the leaf phenology in fall, which may provide further climate limits for aspen tree improvement programs.  Further studies on the cold hardiness of aspen provenance against local environment stresses as well as the related genetic variations are necessary.  

This is a course project website, and the datasets are not for public use. For more information please contact with  Chen (Klaus) via [email protected]. Thanks for visiting.