Coastal Douglas-fir and western hemlock breeding programs began in the late 1960s with the selection of better trees from natural stands throughout the coastal area. Extensive breeding and testing of these selected parents was carried out to learn more about genetic diversity patterns and performance stability, and to identify which parent trees produced offspring with superior performance potential.
The testing programs allowed identification of superior parents from the original selections made in natural stands (Table 1). Information on the long-term growth and yield of offspring from these parents is needed to better predict volume and value gains relative to natural-stand seed. Data are also needed to assist with the adjustment of growth models to account for genetic gains. The first series of trials to provide this information for Douglas-fir and western hemlock was planted in 1992.
Keywords: Genetic Gains, Realized-gain, Douglasfir, Western Hemlock.
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Updated April 13, 2007