摘要： Tree and stand volume estimates are relevant for forest inventories, forest sales and carbon stock evaluations. Forest practice commonly uses generalized stem wood volume functions. However, such generalized approaches neglect the stem form in detail. Hence, trees of a given species with the same diameter at breast height (??1.3) and height (h) are always assumed to have the same form factor and thus the same volume. This case study focused on stem form variation of Picea abies due to competition effects. Using terrestrial laser scanning (TLS), we measured the stem shape of 868 trees from a long-term spacing and thinning experiment in Germany. The plots covered a broad density range. We analysed the effect of competition and compared the TLS- with conventionally determined stem volume estimates. TLS-based volume estimations showed that the lower the competition, the lower the tree volume with a given ??1.3 and h. Commonly used functions underestimated the volume stock overall by 4.2 %, disregarding any levels. At plot level, underestimation varied from 0.7 to 7.0 %. At tree level, the volume was over- and underestimated by -10 to +10 %. The more precise the examination, the more suitable the application of TLS for enhancing volume estimation.