PREPARATION AND CULTIVATION OF THE SOIL 

 FOR THE PURPOSE OF CONSERVING MOISTURE 



By J. T. CRAWLEY, 



You are all agreed as to the important role played by water in 

 the production of all crops, and especially in that of sugar cane. 

 Without an ample supply of water whether from irrigation or rainfall 

 it is impossible to grow satisfactory crops of cane, and it is quit^. im- 

 portant to know how to preserve the moisture in the soil after it has 

 been secured. Eighty inches of rainfall is sufficient to produce good 

 crops, providing all, or the greatest part is utilized — that is, providing 

 il falls with comparative regularity, and that your methods of culti- 

 vation are such as to preserve it for the uses of the crop. If these 

 eighty inches fall irregularly, that is in heavy storms, with long 

 periods of drouth intervening, it may be insufficient. When drouths 

 come, as the present one, long continued and severe, it emphasizes the 

 fact that every means possible should be used to mitigate its evils. 

 After the drouth has come and the cane is dying there is but little 

 in the way of cultivation that can be done. But systems of preparation 

 of soil and cultivation can and should be adopted that will tend to 

 make drouths less severe. 



What I am going to say is at the very foundation of agricultural 

 science, facts and principles so well established as to seem elementary 

 and simple. 



It is much more important that the water coming as rainfall, that 

 costs nothing, neither for the supply nor fur the application of it. be 

 utilized, than that you should provide expensive systems of irrigation. 

 There are two distinct questions, iirst, how shall we secure the 'ab- 

 sorption of the water by the soil and second, how shall we prevent its 

 being evaporated from the soil after it has been absorbed. 



Absorption of innter hy koHk.— The amount of water that a soil 

 can absorb depends on two principal factors. In the first place, it 

 depends on the size and nature of the particles composing the soil, 

 and in the second place on the arrangement of these particles. The 

 water is taken up in the spaces betwen the particles, and the 

 greater the space between these ,>articles, the greater will be the 

 amount of water absorbed. 



Assuming that all soil particles are spherical, it has been calculated 

 that with thi! closo-^t po/.sible ari'angement of the itarticles with re- 

 ference to each other, thofe would be a pore space between these 

 particles of 25.9.5 per cent ol| the volume of the soil, and a soil of this 

 kind could take up -i.") 9,5% of water. If however, these particles be 

 arranged so as to give the greatest pore space, the soil could absorb 

 74.05% of water. Now on standing unmoved for a long time the soli 

 particles become packed together with but little pore space, and in 



