Hemlock, eastern Tsuga canadensis

Mannose-containing Hemicelluloses in the Wood of Eastern Hemlock (Tsuga canadensis) ... 

Honey locust Gleditsia tricanthos L.) 21 Eastern hemlock (Tsuga Canadensis L. Carr) 33... 

Two examples are illustrative Shortly after the turn of the century, one of the ten largest companies in the United States was totally dependant upon extractives for its raw material (23). The Central Leather Company, successor to the United States Leather Company, had tanneries scattered all over the state of Pennsylvania, each of which extracted tannin from the bark of the eastern hemlock Tsuga canadensis). Today not only is it the only one of the ten companies no longer in existence, but there is not a single producer of native tannin in North America. 

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