Messier, C. and J.P. Kimmins. 1992. Growth of western red cedar seedlings in relation to microtopography, forest floor nutrient status, and fireweed and salal on clear-cut sites in coastal British Columbia. Can. J. For. Res. 22:273-278.

The growth of western red cedar (Thuja plicata) seedlings was studied in relation to microtopography, to forest floor nutrient status, and to fireweed (Epilobium angustifolium) and salal (Gaultheria shallon) abundance on 4-year-old logged and burned sites dominated by salal on N. Vancouver Island, British Columbia. The purpose of the study was to determine some possible factors at the microsite level that influence the growth of T. plicata on recently clear felled sites. Total height and root collar diameter of T. plicata seedlings planted in 1987 were measured in April and September 1987, 1988 and 1989. Visual estimates of fireweed and salal cover were made in 1-m2 plots in July 1989. T. plicata growth and fireweed abundance and height were significantly greater in depressions than on flats and mounds, but these differences were not related to any major differences in forest floor pH, cellulose decomposition, total N and P, or available NH4, NO3, and phosphate P as measured using resin bags. The ecological significance of the results are discussed. It is suggested that T. plicata is relatively insensitive to changes in forest floor nutrient availability and that fireweed growth is not directly influenced by nutrient availability 4 years after logging or burning on these sites.