Heterogeneity in a poplar stand and estimation of the mean volume index

For a  small poplar stand of 81 Robusta trees (2 years old), contour mapping and  trend surfaces are calculated. These statistical techniques can be  informative for showing heterogeneity and can be helpful for estimating the  mean of the parameters concerned. They can yield better estimates than random sampling in the stand. As  parameter, the Volume Index is used for demonstrative purposes.