Seed transfer guidelines for Douglas-fir in Western Montana

Summary of transfer guidelines for Douglas-fir in western Montana. Guidelines based on adaptive differentiation found in juvenile trees related to physiographic characteristics and elevation. The author details both discrete and floating transfer guidelines for western and eastern provinces because elevational clines are steeper in the west (400') than in the east (800'). Small geographic and narrow elevation limits to transfer may be inappropriate, however expanding limits of transfer increases risk of maladaptation (reduced growth rate and increased cold damage). Regression techniques accounted for 81% of the variance in 3-year height of 54 Douglas-fir populations from western Montana. Seed transfer guidelines are developed from patterns of adaptive variation.