The heartwood and sapwood of Pinus sylvestris L. were analysed using s
imultaneous taper models for stem without bark and for heartwood. Sapw
ood area tapered monotonically from the base to the top of the stem. B
elow crown base the stem tapered more slowly than in the crown. The pr
oportion of heartwood in the tree stem was higher in dense sample plot
s than in sparse ones and also decreased significantly with increasing
relative size of a tree in a plot. Height at crown base correlated si
gnificantly with the proportion of heartwood, stand density, and relat
ive size. Height at crown base was the most effective additional indep
endent variable for predicting sapwood basal area at crown base when d
iameter at breast height and tree height were measured. Connected with
diameter at breast height and tree height measurements, width of the
sapwood at breast height explained significantly better sapwood and he
artwood volumes than height at crown base.