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BLACK SPRUCE (Picea mariana)
WHITE SPRUCE (Picea glauca)
Other names: swamp spruce, bog spruce; skunk spruce, Canadian spruce

POOR TO GOOD

These spruces are found in the Great Lakes region, through Canada, and are most prevalent in the interior regions of Alaska. Black spruce grows profusely in swamps, bogs and muskegs, and may be the only tree available in those locations. It is a slow growing tree and may be only 5" or 6" diameter when 400 years old. The white spruce favors wet conditions but does grow on higher lands and is usually larger than the black spruce and may be cut for lumber. It grows faster but has a shorter normal life span. 

The original blazes on these spruces are seldom healed over. Fire may burn the open blazes with little trace of scribing remaining though it may be detected by side lighting. The bark is thin, the wood is soft and decays rapidly when on the usually wet ground. The root system is shallow and leaves no stump hole. Very few of these trees are recovered in the Great Lakes region, indicating they are not desirable bearing trees, if better species are available. Alaska finds them to be better than tamarack, birch or aspen. 

Select trees at least 4" to 6" diameter. Keep the blaze small, just large enough to accommodate the required scribe marks. Blaze care- fully to avoid separating the bark from the cambium layer, and smoothly drained at the bottom. Paint thoroughly but not excessively. Releasing may be necessary in dense stands. Prune off the lower limbs to a height of about 4 feet on the smaller trees.