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constituent in the soil. To this there is one answer, which, though 

 not entirely by a long way preventing the loss of nitrogen, yet 

 will very materially reduce it. This is the use of green manuring 

 crops, The nitrates are at their maximum in the soil before the 

 rains fully break, the early rain, which just moistens the soil but 

 does not cause the drains to run, only makes their formation more 

 rapid and hence increases the quantity, A crop should therefore be 

 sown at the first opportunity in spring (that is, as soon as the land 

 is moist enough to germinate the seed) and be hoed in, say in the 

 middle of June. By this means a considerable quantity of nitrogen 

 will be retained in the soil which would otherwise be lost. I will 

 defer the consideration of the most suitable crops for this purpose 

 till the next chapter, but here I would insist most strongly on their 

 utility as a means of preventing part, at any rate, of the loss of this 

 most expensive ingredient of the soil, 



It has been suggested that allowing a growth of weeds would 

 be just as much to the purpose as sowing a special green manuring 

 crop, as these would retain the nitrates just as well. To a certain 

 extent this would be true, but not altogether, for the natural weed 

 herbage is only very shallow-rooted, the very common Ageratum 

 (" cold weather weed" of Assam, " ilami " of the Dooars), or many of 

 the natural grasses being examples, and as their faculty for retaining 

 nitrogen is limited by their root range, the effectiveness of such 

 plants is not very great, not nearly so great as many which could 

 be specially sown. Further, even were they equally effective, it 

 must be recognised that the growth of a miscellaneous lot of plants 

 is distinctly risky, for many of the pests of tea find shelter in one 

 or other of the weeds, and are thus enabled to propagate and go 

 on to the tea at a suitable opportunity. The whole principle of 

 allowing weed growth on a garden in Assam is distinctly wrong, 

 they are themselves a danger, and whatever functions they do 

 perform can be carried out better by the growth of a definite crop 

 of known value. 



LOSS IN VALUE OF NEWLY CLEARED LAND. 

 The loss in organic matter and nitrogen is most active in newly 

 cleared land, There the conditions are usually most favourable 

 (on good tea-soil) for the growth of the organisms producing nitrates, 

 and the organic matter is in a very suitable state as a medium for 

 their activity. Hence, if such land be left uncovered for a year 



