Development of focal point seed zones for white spruce in Northern Ontario

Report

Transfer Guideline: Recommendation

White spruce (Picea glauca [Moench] Voss.) is distributed widely throughout the boreal forest of Ontario and the rest of Canada. Ecologically based management of this species requires an understanding of its patterns of adaptive variation. The development of focal point seed zones will assist in properly matching seed sources and planting sites. To develop focal point seed zones of white spruce, one hundred and thirty two provenances from Ontario and western Quebec were established at a greenhouse and five field trials throughout Ontario. Growth and phenological variables were measured over two growing seasons and selected variables regressed individually against geographic and climate variables to assess whether they exhibited adaptive variation. Principal components (PC) analysis was used to summarize the main components of variation. The first PC mainly represented growth potential. PCs 2 and 3 mainly represented phenological traits. PC factor scores were regressed against climate variables and the resulting equations were used to model the PC axes. Models were converted to spatial data and reproduced as contoured grids using GIS. For any given point in Ontario PC axis grids can be standardized and intersected, creating zones of adaptive similarity to that point. Focal point seed zones created for 20 example points selected from across the province show strong latitudinal trends and more regional longitudinal trends. Seed transfer for white spruce across traditional site region boundaries may be possible in most of north-central and north-eastern portions of Ontario.