NUTRITIONAL QUALITY AND TANNIN ASTRINGENCY OF BROWSE IN CLEAR-CUTS AND OLD-GROWTH FORESTS

Compared nutritional quality and morphology of 4 browse forages of black-tailed deer Odocoileus hemionus columbianus and Roosevelt elk Cervus elaphus roosevelti in clear-cuts and old-growth forests on the Olympic Peninsula, Washington. Browse in old-growth forests had a greater proportion of leaves, was more succulent, and had higher percent crude protein than browse in clear-cuts. There was no consistent pattern of difference in fiber content and digestibility between forest types. Tannin astringency was greater in clear-cuts. Because tannins decrease digestible protein (DP), DP was more available in shrubs grown in old growth than in clear-cuts; little DP was available to cervids browsing in clear-cuts. Retention of patches of old growth in the Pacific Northwest will provide optimum year-round habitat for cervid foraging. -Authors