COMPOSITION OF FALLEN LEAVES OF FOREST TREES 

 AND THEIR QUANTITIES 



By SHIGEMASA MORJYA, Chemist of Forest Experiment Station 



In many localities fallen leaves are collected and used either as fuel 

 or for other purposes. The country people generally consider only how 

 to use these waste products for their own profit. Such a time-honored 

 usage should, however, be discredited, since, from the stand point of 

 forest economy, the fallen leaves form the principal source of nutrients 

 for the growing trees and also exert a beneficial effect by retaining water 

 and protecting the excessive evaporation of moisture from soil. 



I. Composition of Fallen^ Leaves of Forest Trees 



To ascertain the manurial value of fallen leaves of forest trees, the 

 fallen leaves of Sugi (Criptomeria Japonica) , Akamatsu (Pinus densi flora) , 

 Kuromatsu (Pinus Thunbergii), Kunugi (Quercus serrata), Konara 

 (Quercus glandulifera) , and Shirakashi (Quercus Vibrayeana) grown at the 

 Experiment Station were duly collected and analysed in the usual way : — 



(a) Nitrogen. 



The most important ingredient of fallen leaves is no doubt nitrogen. 

 Among conifers, the Sugi leaves are richest in nitrogen containing 0.972% 

 or about 1% of the air-dried substance. Sugi is followed by Akamatsu 



