Critical nutrient concentrations and DRIS norms for mid-rotation Cedrela odorata L. trees

Abstract

Nutrient diagnosis helps increase fertilizer use efficiency in forest plantations as well as economic profits and ecological benefits. Two of the methods commonly used for diagnosis of the nutrient status are critical nutrient concentrations and the Diagnosis and Recommendation Integrated System (DRIS); however, no studies exist that show the critical values or DRIS norms for Cedrela odorata (red cedar); which is an important tropical tree species. The aim of the present study was to develop a set of critical nutrient concentrations and a set of DRIS norms as well, for C. odorata at the mid-rotation stage. The study was carried out by selecting 74 trees located over the species natural distribution area in Mexico, on which diameter increment and nutrient concentration was recorded from July 2017 to January 2018. A set of critical nutrient concentrations and one more of DRIS norms were developed. In a second phase of the study, both nutrient standards were verified by using an experiment installed within a red cedar mid-rotation plantation. The experimental design was a complete randomized, with a 3×4 factorial arrangement of treatments, where the factors corresponded to the application of P and K, respectively. A set of critical nutrient concentrations and a set of DRIS norms for C. odorata at its mid-rotation stage are exhibited in this paper. The verification process indicates that both reference sets correctly predict nutrient status of mid-rotation red cedar trees.