70 



taken as the final sample upon which the analyses are based — it follows 

 that in a given area of land considerably more nutritive matter is ac- 

 tually present than in a land of coarser texture, where the fine earth 

 might amount to only 30 to 40 per cent of the whole, even though 

 the latter appeared on analysis to be somewhat richer. 



HAWAIIAN SOILS. 



Below is given the average analysis of soils in the Hawaiian Islands : ' 



Omitting the third decimal place as a rather unnecessary refinement in soil 

 analysis, it will be noted that these Hawaiian soils, which under intensive cultiva- 

 tion and irrigation are the most highly productive in the world, run from one 

 and a half to two times higher in potash, phosporic acid, and nitrogen than the 

 general average of soils from Negros, although their superiority is not so marked 

 when compared with the richer districts of San Carlos and Bais. In lime they 

 are very much lower. 



EGYPTIAN SOILS. 



Analyses of the narrow strip of alluvial soil along the Nile, in upper Egypt, 

 where much sugar cane is grown, are given by Tiemann:' 



Although these are decidedly richer in every respect than the famous Hawaiian 

 soils, yet they are spoken of by Tiemaim as being "exhausted" and in need of 

 artificial fertilizers, a fact which would tend to support the theory that the so- 

 called "exhaustion" of soils is more often than not due to other causes than simply 

 a lack of sufficient mineral plant food. 



' Report of Work of the Experiment Station of the Hawaiian Sugar Planters' 

 Association, Div. of Agr. and Cheni. Bull. No. 15, 1905, p. 7. 

 *The Sugar Cane in Egypt, p. 18. 



