Fig. 4

Vertical variations of basic specific gravity (BSG) and relative water content of lumens (R W C _L ) per species: (A) ground level (< 0.50 m), (B) stem bottom (1.30 m for softwood species, 2 m for hardwood species), (C) below crown base height, (D) inside the crown. For several trees, there was no measurement in either of the two upper compartments. The bracketed numbers below the whiskers indicate the actual number of trees for each box. The letters above boxplots identify the statistically significant different groups according to pairwise t tests