J. Karchesy
E. E. Starkey
M. P. Gonzalez-Hernandez
2003
<p>Tannins<span> are secondary metabolites that may influence feeding by mammals on </span>plants<span>. We analyzed </span>hydrolyzable<span> and </span>condensed<span> </span>tannins<span> </span>in<span> 30 </span>plant<span> species consumed by livestock and deer, as a preliminary attempt to study their possible implications on browsing and grazing </span>in<span> </span>forest<span> ecosystems. Heathers (<i>Ericaceae</i>) and </span>plants<span> of the Rose (<i>Rosaceae</i>) family had </span>tannins<span>, while forbs, grasses and shrubs other than the heathers did not show astringency properties. We found the highest </span>tannin<span> content of all the species </span>in<span> <i>Rubus</i> sp., with the highest value around 180 mg TAE/g dry weight </span>in<span> spring. <i>Potentilla erecta</i>, <i>Alnus glutinosa</i> and <i>Quercus robur</i> were next with 57 to 44 mg TAE/g dw. Total </span>tannins<span> </span>in<span> heathers ranged from 22 to 36 mg TAE/g dw. Levels of </span>condensed<span> </span>tannins<span> were higher than </span>hydrolyzable<span> for most of the species. Only <i>Betula alba</i>, <i>Calluna vulgaris</i>, <i>Pteridium aquilinum</i> and <i>Vaccinium myrtillus</i> had 100% </span>hydrolyzable<span> </span>tannins<span>. </span>Tannin<span> content of the species changed seasonally with highest values during the growing season, corresponding to late winter or early spring, depending on the species.</span></p>
application/pdf
10.2307/4003837
en
Society for Range Management
Research observation: Hydrolyzable and condensed tannins in plants of northwest Spain forests
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