Use of phenology for examining provenance transfers in reforestation of Douglas-Fir.
Abstract
Describes the development of a simple predictive model (based on two sets of equations) that uses the timing of vegetative bud burst to examine the response of seedlings of Pseudotsuga menziesii to seed transfer during reforestation. The first equation was derived from data from a greenhouse experiment with seedlings of 44 provenances, grown from seed collected near weather stations in W. Washington, Oregon and N. California. The equation related mean number of days to bud burst of terminal buds to an exponential function of mean daily temperature. The second equation, based on data over a 21-year-period from each weather station, related mean daily temperature to the time in days after 22 Dec. Dates of bud burst were predicted for hypothetical populations along elevational and latitudinal transects. Although it was not possible to test predictions objectively, they were generally in accord with A.D. Hopkins' (1918) bioclimatic 'law' and other available evidence. Results of a hypothetical transfer indicated that moving seed in E.-W. directions was likely to be more maladaptive than moving seed an equivalent distance from N. to S. [Cf. FA 35, 2188]