August, 1910.] 



129 



Live Stock, 



if it can be demonstrated to his satis- 

 facion that his rice laud can be made to 

 produce another crop that will benefit 

 him and his cattle, he will not be slow to 

 grow it. There are several kinds of 

 fodder plants that it may be possible to 

 raise profitably on the average rice field 

 during the time it is left bare between 

 crops. 



In Italy, where they grow a consider- 

 able aiea of rice, it is a common thing to 

 notice large tracts of rice land under 

 Indian corn plants grown close together, 

 £ nd these being cut down or pulled up 

 and stacked for use as cattle food. 



A Ceylon rice field can be made to 

 pioduce a plentiful crop of Indian coin 

 plants within six weeks of sowing. The 

 crop of fodder thus obtained will be 

 a considerable one, amounting to an 

 average of over 5,000 lb. when dry. 

 These possibilities require investigation, 

 and once their utility is established, the 

 feeding and maintaining of agricultural 

 cattle will not present so many diffi- 

 culties as at present. 



At one time large herds of agricultural 

 cattle in the villages were killed through 

 the ravages of rinderpest, and we have 

 had recent experience of the damage 

 that is caused by the spread of this 

 disease. However, we are more fortun- 

 ate than many other countries where 

 cattle disease prevails, our death roll 

 among cattle during the last year, in- 

 cluding those that died of rinderpest, 

 hardly exceeding 5 per cent. Withpresent 

 quarantine arrangements affecting im- 

 ported cattle, and the systematic work 

 done by the Veterinary Department, it 

 is not inconceivable that within the next 

 two or three years we may find our- 

 selves in the very fortunate position of 

 being entirely free from the scourge 

 which has hitherto been the cause of 

 such serious loss to the cattle owners of 

 the Island. 



The problem of the future of agricul- 

 tural cattle in Ceylon is a simple one if 

 it is properly understood. We require 

 a supply of cattle for maintaining the 

 cultivation of rice, but the possession of 

 cattle need not prove a source of trouble 

 and loss to our neighbours. 



SCIENTIFIC AGRICULTURE, 



THE CONSERVATION OP THE 

 FERTILITY OP THE SOIL. 



By A. D. Hall, m.a., p.b.s., 

 Director of the Rothamsted Experi- 

 mental Station. 



(From the Journal of the Board of Agri- 

 culture, Vol. XVII., No 2. May, 1910.) 

 In considering the value of various 

 systems of farming it becomes a matter 

 of prime importance to get some idea 

 of how far the fertility of the land is 

 being preserved, and whether the suc- 

 ceeding generation of farmers is likely 

 to find the cropping power of the soil im- 

 proved or deteriorated by the treatment 

 it has received. It is pretty clear that in 

 many parts of the world the natural 

 riches contained in the virgin soils are 

 being rapidly depleted; this may be 

 deducted from the constant westward 

 movement of certain classes of farmers 

 in the United States and Canada, though 

 in some part9 of America tne soil seems 

 to be able to yield good crops for an 

 indefinite period; on the other hand, 

 many European soils have reached a 

 sort of constant level of production and 

 get neither richer nor poorer, although 

 they have been in cultivation for many 

 centuries. We also occasionally hear 

 of worn-out soils, but it would be more 

 correct to say badly managed or spoilt 

 17 



soils, because there is no evidence that 

 the production of a soil ever declines 

 under suitable treatment. 



In tracing changes in the fertility of 

 soil, we may content ourselves with 

 following up the changes in the amount 

 of nitrogen present, because though 

 phosphoric acid, potash, and lim9 are 

 important factors in plant nutrition, 

 these elements are not susceptible to 

 the gains and losses from external oper- 

 ations like cultivation, by which the 

 stock of nitrogen is so greatly affected. 



There are various processes at work 

 which will diminish or add to the stock 

 of nitrogen in the soil, and these may 

 be summarised as follows : — 



(1.) The growth of plants simply re- 

 moves some of the nitrogen that has 

 reached an available form, and if the 

 crop is taken off at harvest there is so 

 much direct loss to the soil. As it may 

 also be accepted that the plant itself, 

 apart from bacterial action, neither con- 

 verts any of the combined nitrogen it 

 obtains into gas, nor brings into combin- 

 ation any of the free nitrogen of the 

 air, there is neither gain nor loss of 

 soil nitrogen when the growth of the 

 plant is returned to the soil. 



(2.) Va rious bacteria are capable of 

 bringing atmospheric nitrogen into com- 

 bination, and so increasing the stock of 

 soil nitrogen. They may either live in 



