Nutrition Research: Some Problems of the Total Tree Approach
1963
Madgwick, Herbert A. I.
Total tree analysis can yield an inventory of nutrients within a stand and, indirectly, a measure of nutrient uptake. The latter may be obtained more accurately by a combination of methods. Stand weight is best estimated by relating tree size to weight from large, intermediate, and small trees. Accurate estimation of nutrient concentrations requires sampling from additional size classes. Attempts to sample average trees yield biased estimates. The number of sample trees required per stand varies with stand characteristics. Five trees per plot gave average prediction errors between 7 and 23% for different parts of red pine trees. To be commensurate with the field work required, laboratory techniques should be of high quality and include analysis for a wide range of elements. Although too cumbersome for a diagnostic tool and, probably, too damaging for use in most permanent sample plots this technique can yield much basic information on stand nutrition and related problems.
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