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Edible Products. 



If, in the cold weather, the subsoil between two and three feet deep contains 

 more than one-third of this amount (or perhaps one-half with a sandy or light soil) 

 calculated on the dried soil, it will be most probably waterlogged in the rains, and 

 needs subsoil drainage badly. The next test can be still more easily applied by 

 digging a hole in the land after rain has been steadily falling for some days at the 

 height of the monsoon. If, at this time, the water is within three or even four feet 

 of the surface, a case for immediate deep drainage has been made out. A still 

 further test depends on the rapidity with which the water falling on the surface 

 disappears into the land. Observation on this point is only valuable after there has 

 been much rain for some days, and the soil is thoroughly wet. In any case two 

 hours after the rain ceases, the surface should be free from standing water. 



If the land answers satisfactorily the tests above set down, I think that it 

 may be concluded that the cause of the deterioration lies elsewhere than in the 

 drainage ; if not, systematic drainage must be undertaken. It would lead us too 

 far to go here into the methods by which the drainage must be done, and for this 

 I must refer the reader to the chapter on the drainage of tea gardens in "The 

 Pests and Blights of the Tea Plant" (second edition,) by Sir George Watt and 

 the writer, published in 1903. 



PHYSICAL, CONDITION OP THE SOIL. 



But if the drainage is satisfactory, is the physical condition of the soil and 

 subsoil as it should be ? In other words, is the soil in good ' tilth ' not merely on the 

 surface, but for some distance into the land as well ? If not, is the nature of the 

 soil to blame, or is the condition solely due to lack of adequate cultivation ? The 

 first test to be applied in this connection is pressing of a stick down into the land. 

 It will most likely be easily forced in to the depth of four to six inches in any 

 garden, but in one where the soil conditions are good there should be no trouble 

 in driving it by pressure of the hands alone to eight or ten inches, and sometimes 

 even to fifteen inches deep. If such a stick shows evidence of a hard layer (other- 

 wise ' hard-pan ') at a depth of less than ten to twelve inches, it is evident that the 

 condition of the soil needs improvement. A second test is furnished by the 

 condition of the roots themselves. If they are flattened out, if all the rootlets which 

 tend downward become rapidly small and stunted, if the whole rootlet develop- 

 ment is a surface one, this affords a strong reason for supposing that the subsoil 

 conditions need improvement in a physical sense. 



The soil improvement needed may be merely more and better light hoeing 

 In quite a number of tea estates, in the Duars for instance, which have come under 

 my notice, and where the tea is said to be ' going back,' this is almost certainly 

 the case. The precise cause of the effect which this light cultivation produces 

 on the bushes has never been entirely explained. Its primary object is, of course, 

 always held to be the burial and destruction of jungle growth. But it must do 

 more than this, for, in places as we have noted above, where jungle growth is 

 very small, the effect of lack of cultivation is equally obvious in a rapid yellowing 

 of the bushes and a speedy increase in disease. In a large measure, no doubt, the 

 cultivation is useful because it keeps the surface soil loose, and allows the tea 

 rootlets thus easily to push, through it. There is, we fancy, something even beyond 

 this. In heavy soils, at any rate, there is always a large amount of plant food in 

 the soil that no plant can use, as it is not in a condition in which it is absorbable by 

 vegetable growth. This becomes only gradually available in the soil when it is 

 exposed to atmospheric influences. A large quantity of the phosphoric acid and 

 potash in heavy soils is usually in this unavailable condition, and it needs the 

 exposure caused by the regular hoeing to make them ready to be absorbed by plant 

 life. This is the more probable because as land gets older and longer under tea. 



