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WESTERN HEMLOCK (Tsuga heterophylla) MOUNTAIN HEMLOCK (Tsuga mertensiana)
Other names: hemlock, gray fir, sil~er fir, Alaska
pine; also alpine spruce, and may have
been confused with spruce or fir.

FAIR TO VERY GOOD

The western hemlock is found from northwestern California north to the Kenai in Alaska along the Pacific slope and in northern Idaho. Mountain hemlock is usually confined to the higher open ridges near timberline or deep snow regions. Locality determines the durability of the tree. In the rain forest conditions the blaze is usually decayed though the tree is still alive and relatively sound. In ideal conditions it has been found completely healed and the blaze indiscernible, but this is rare. Stumps rapidly decay to a mulch. Fire will completely consume a dry stump, dead or fallen tree. The butt of the larger trees are frequently deeply fissured making detection of the blaze difficult before opening. The hemlock is thin barked and probably was seldom bark scribed. 

Mountain hemlock is more durable in the drier and alpine environment and has been found with the blaze face intact with scribing weathered. There is no "pitch face" on either hemlock. 

When used for a bearing tree keep the blaze small and well drained. Blaze through the sapwood and keep the bottom of the blaze higher than on most other trees. Young trees 8" to 12" are usually best. If a large hemlock is used select an outer "rib" of the swelled butt for the blaze. Western hemlock frequently takes root in an old stump or log and large roots reach down to the ground level. A large root seems to be more durable than the tree proper. Hemlock knots are very hard and will damage an axe when chopping into them and may break the scribe also. Paint the blaze thoroughly to protect against decaying fungus.