Seasonal Differences in the Element Content of Wyoming Big Sagebrush

Abstract

Concentrations of 30 elements in samples from a stand of Artemisia tridentata subsp. wyomingensis Beetle & Young were determined for young and old tissue in September, January, April, and July, 1975-76. Elements with similar seasonal trends were grouped. Changes in the Concentration of the major essential elements (Ca, Mg, P, K, and S) with season directly reflect phenological events which alter the proportion of leaf-to-stem tissue in the samples. In general, the element composition of younger tissue fluctuates more, has higher concentrations, and shows greater differences between seasons than older material. These data stress the influence of season, on the element concentrations in plant tissue and underscore the need for caution when comparing sample data with established element concentration baselines.