| Popis: |
Data from four studies of trace elements in whole trees of Pinus radiata D. Don in the central North Island of New Zealand have been combined in an attempt to generalized nutritional status of boron, copper, manganese and zinc in live branches, stemwood and stembark. Concentrations of B, Cu and Zn tended to decline with increasing tree age and increasing diameter, except in the case of branch Cu which was affected by aerial applications of cooper fungicides. Manganese concentrations in woody tissue increased with age in unthinned stands, decreased following thinning and then increased again. Data were available for Mn and Zn for 19 plots ranging in age from 2 to 29 years. Regressions accounted for 74–88% of the variation in mean Zn concentration. |
