Fig. 3

Cumulative annual ring width and basic density in relation to annual ring number from pith. CRW, cumulative annual ring width; BD, basic density. The circles in grey color indicate values in each sample tree. Regression curves indicate the formula with the fixed-effects parameters (Table 5) and random effects of family or block in sites for the best-fitted models selected by AIC (Table 4). The vertical solid lines indicate the annual ring number from the pith in which the rate of change in basic density reached less than 1% (13.9 years at Hitachi and 12.5 years at Kiso)