| dc.description.abstract | Provenance tests in Ontario have been used for decades to evaluate the optimal
seed sources for different environments. Understanding the genetics, adaptations and
selection pressures of tree species using provenance testing will help determine future
favourable planting locations. The growth of many tree species will be adversely
affected by climate change, as most woody plant species cannot keep up with the rate of
change. White spruce (Picea glauca (Moench) Voss) is a widespread, economically
important tree species for the Canadian forest industry. Being a widely distributed
species, Ontario has many white spruce provenance test trials with sources from across
the province and the country. Provenances from across Ontario have been planted at a
Kakabeka test site to determine the top performing seed sources. This thesis explores the
variation in height between provenances at this test site to determine the climatic
variables which are most significantly related to this intraspecific variation. The top
performing provenances at the Kakabeka site originated from southern Ontario and
Quebec, and the worst performing provenances mostly originated from northwestern
Ontario. Provenance and block effects explained a significant portion of variation in
mean heights. Growing season climate variables showed a significant relationship to
height variation among provenances. The best predicting variables were mean annual
solar radiation (MAR) and Hargreaves reference evaporation (Eref). This study provides
valuable data to determine the optimal seed sources for current climate conditions. | en_US |
