Days to bud break and freezing tolerance of `Chilcotin', `Chilliwack', `Meeker' and `Willamette' red raspberry were measured during the 1990-1991 winter and at monthly intervals from mid-September 1991 through mid-March 1992. Canes were harvested from the field and cut into two-bud samples which were either frozen in laboratory tests or held with cut stem ends in water in a controlled environment chamber and monitored daily until bud growth was observed. Viability was estimated by visual browning after exposure to controlled laboratory freezing treatments. In general, freeze test results indicated `Meeker' and `Willamette' were not as hardy as `Chilliwack' and `Chilcotin' in late fall and midwinter but retained their hardiness longer in spring. Results for 1990-1991 indicated the greatest delay in days to bud break occurred in midwinter.
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