A comprehensive literature review of the factors affecting the survival of planted Douglas-fir seedlings is presented. Original data from operational planting trials was analyzed to determine the effect of some seedling, planting and environmental factors on survival. The use of 2+1 stock was found to result in increased survival of fall-planted seedlings, but not of spring planted seedlings. 1+0 stock showed comparatively good survival when spring-planted on sites with little brush and/or

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... competition. The size of planting stock, and a subjective assessment of grade were not found to be related to survival after one growing season. Fall lifting dates from October 15 to December 2 were analyzed in relation to survival using regression analysis. Early-lifted stock was found to result in lower survival than the later-lifted stock. Lifting date had no significant effect on the survival of spring-planted seedlings. Planting dates from February 10 to June 10 in the spring and from October 14 to December 2 in the fall were analyzed in relation to survival using regression analysis. Survival was found to be significantly improved with later fall planting dates and early spring planting dates. Length of storage had no detectable influence on survival. The nursery origin of the seedlings was found to be significantly related to survival. Where ground cover competition was severe, slash-burning resulted in increased survival; where ground cover competition was light or non-existent, slashburning resulted in reduced survival. Heavy ground cover competition reduced the survival of both spring and fall-planted seedlings, except on north to east aspects. Elevation and aspect of the planting site were both found to be significantly related to survival. Planting in thick duff reduced the survival of spring and fall-planted seedlings. The survival of fall-planted seedlings was also reduced by planting in rolling topography, and on steep south to west aspects. Planting during sunny weather resulted in reduced su [...]