Abstract
The effect of spacing shape is one of the major problems of tree growth modeling. Nelder (1962) proposed an area fixed, shape change plot design (design Ib) to solve the spacing-shape problem. We analyzed periodically measured data from a design Ib type plot of Picea glehnii planted in the Hitsujigaoka experimental forest at the Hokkaido Research Center of the Forestry and Forest Products Research Institute. As a preliminary result, spacing shape affected growth in both DBH and height.
