Thirty-seven seedlots of western white pine (Pi nus mont i col a Doug. ex. D. Don) were tested for frost hardiness to determine how transferable seed would be from different seed sources within white pine's coast and interior ranges in British Columbia. Twenty-nine seedlots represented the coast and interior of British Columbia (BC), two were from coastal United States (US), three were from interior US and three were hybrids between interior US and interior BC parents. Detached needles were exposed to a series of freezing temperatures in a programable freezer and relative hardiness was calculated as the length of injured needle expressed as a percentage of total needle length 10 days after freezing. Seasonal progress in hardening was tested using five dates in the autumn of 1989. Seedlings were maintained at the University of British Columbia nursery. Testing also was carried out from samples collected on separate dates from Nakusp in the BC interior and from Ladysmith, a coastal BC site. There was a statistically significant (p<0.0l) regional difference between the BC coast and BC interior sources in all test runs, excluding the first UBC run and the Ladysmith run. In the runs where regions differed significantly, the difference in percent damage response of needles to freezing was approximately 20%. Measurements of shoot growth phenology were planned as an additional component of growth rhythm. Injury from uncontrolled freezing forced a change of objective to evaluation of genetic differences in recovery from freezing. Those evaluations did not reveal genetic differences in recovery. / Forestry, Faculty of / Graduate

The relationship between clone and cone color in western white pine, Pinus monticola Douglas, to attack by the mountain pine cone beetle, Conophthorus monticolae Hopkins, was studied in the Sandpoint Seed Orchard, Idaho. A positive relationship was shown to exist during a 5 year field evaluation. Cone beetles were found to prefer dark colored cones and to attack certain clones at a higher rate than others. Laboratory dissections did not indicate that cone color affected oviposition, brood development or brood mortality. Olfactometer experiments demonstrated that olfactory stimuli are involved in the cone beetle attack sequence. Visual cues relating to cone color may be involved in the initial long range host orientation of attacking beetles.