E.P. 1121.01 - Effects of red alder density on conifer growth and nitrogen availability

Objectives:

• To document the effects of differing amounts of red alder on the growth of conifers, under different site conditions.
• To improve understanding of both the competitive and beneficial effects of red alder when grown with conifers.

Location:

East Wilson Creek, Holt Creek, Gough Creek, Waterloo Creek

Contacts:

• P. Comeau
• B. D'Anjou

Abstract:

Marking of plot boundaries and installation of additional signs is required to prevent accidental brushing of the research plots. During 1995 red alder in a portion of one plot (plot 7) at East Wilson Creek was cut by a brushing crew. In this plot approximately 50% of the cut trees resprouted during 1996. Dead trees were replaced with seedlings in November 1996.

Fill planting has been done during the first 5 years to ensure that no major gaps exist in treatment plots. Experience to date indicates a need for good manual screening of planting spots for red alder, since survival is poor when seedlings are planted in undisturbed soil organic horizons (LFH). In addition, red alder seedlings are seriously damaged by any overtopping vegetation.

Fifth year height growth of red alder was similar for the 3 sites planted in 1992 (East Wilson, Gough, and Waterloo). Year three height of red alder at Holt Creek is substantially smaller than that observed at the other sites. This difference results largely from differences in seedling quality and size at the time of planting. Red alder seedlings planted in 1994 were substantially smaller and of poorer quality than those planted in 1992.

Web Presentation:

• http://www.for.gov.bc.ca/hre/forprod/fordyn/projects/ep1121/ep112101/ep112101.htm