The scaling of respiratory metabolism with body mass is one of the most pervasive phenomena in biology. We challenge to clarify the respiratory and growing behavior of Fagus crenata, a dominant species in the Northern hemisphere.
We collected seeds from Mt. Gassan in April 2016 then planted them in two different light conditions, open and shaded sites and measured the whole-plant respiration rate and morphological traits, or mass, surface area, and moisture content of each organ from seeds to seedlings (n=200).  
Only within the period from just after absorption of moisture of the seeds to seedlings before leaf opening, we observed a drastic increment of respiration rate without assimilation.  After main-leaf opening, the respiration rates of seedlings with main-leaves showed negative allometric relation to their body mass.
Thus, we found that a clear shift in scaling exponent from positive to negative in individual respiration to mass on log-log coordinates. In the time course of the shift, we observed a promotion of whole-plant mass at the open site but no difference in whole-plant respiration rates between open and shaded sites at a same individual mass.  Thus, under open and shaded sites, any seedling at a same mass showed same respiration rates. The present results showed that individual respiration rates may be mainly constrained by their individual body mass in the seedling stages.