1 8 FORESTRY OF JAPAN. 



Mesczoic period. The forest lands of Yoshino in Vamato 

 province belong to the archaean formation. In western part 

 .of Honshu, particularly in Chu-goku, the land is mostly com- 



l of granite while the forests in such provinces as Tanha 

 and Tajima stand upon the archaean formation. The central 

 mountain chain of Shikoku belong, as is the case with Yoshino 



in Vamato province, to the archaean formation. A portion of 

 southern Kyushu also belongs to the archaean formation hut 

 the rest is largely composed of igneous rocks. The basic 

 strata of Japan consists of rocks of archaean formation, upon 

 which other strata have been deposited. The volcanic erup- 

 tions in each geologic period have extended over the surface 

 of large areas of igneous rocks, in fact one third of these forest 

 lands consisting" of these igneous rocks. The rock belonging 

 to the archaean formation is granite, and those eruptions of 

 archaean and mesozoic formations have granite strata, por- 

 phyry, diabase, and porphyrite. There are large varieties of 

 rocks belonging to the Tertiary and Ouarternary but the 

 largest area is occupied by andesite and basalt. 



The difference in the strata naturally causes variations in 

 the soil both in kind and nature affecting to no small degree 

 the growth of forest trees and the formation of forests. 



Coniferous forests covering an extensive area and retain 

 ing the beautiful sylvan features grown by tin- natural regene- 

 ration are mostly found upon the strata of igneous rocks while 



ater part of forests grown up by means of planting are to 

 be found on the aqueous rocks. 



Ja] an's topographical and climatic relations affect the 

 species of forest trees, condition of their growth, and the 



