( 6i., ) 



Japan. Their capacity of al?sorptipn is very great, especially 

 for phosplipric acid. This is due to the presence of ferrous 

 oxide. The physical properties need to be improved by the 

 addition of humus into the soil so as to make them open and 

 frjjable, while aeration gpes on more easily than in the case of 

 .volcanic soils. Generally speaking, though these soils are 

 rich in manurial elements, they are defective in texture, owing 

 to the action of low temperatures. 



Where drainage is good owing to the natural situation or 

 the character of the subsoil, apple and pear orchards have, 

 shown good results, especially wheh the soil contains gravel. 

 The soil becomes very stiff and retentive when wet and split^ 

 into hard blocks when dry. This defect can be overcome by 

 adding humus or by application of lime in proper quantities. ,, 



Amongst the. Tertiary soils, those derived from sandstone 

 are of exceptionally good texturej being not so retentive as 

 the above. Those of conglomerate origin are poor both in. 

 texture and fertility, and need improvements for successful, 

 fruit growing. 



7. OLDER QUATERNARY SOILS. 



During this period, volcanoes seem to have been very 

 active, hence most of the quaternary soils have admixtures of 

 the weathered products of volcanic ashes. They' occur in 

 relatively small areas in this country. They are rich in humus 

 nitrogen, lime and ferrous oxide. While having a strong 

 affinity for phosphoric acid owing to the presence of ferrous 

 oxide, their absorptive capacity for other nutriments is moder- 

 ate. The presence of iron compounds in the soil would tend 

 to hinder aeration and would prove injurious to vegetation. 

 In north Japan lands of this category remain barren as grass- 

 lands or plains. 



The case rather differs in the Old Quaternary soils near 

 Tokio, or in. the so-called "Kwanto plain." Here the soil 

 readily becomes wet and dry, aeration being checked- in the 



