720 The Winter and the Wheat Crop, [march, 



of nitrogen, rarely receives any direct manuring ; its nitrogen 

 has to come from the residues of previous crops, and since the 

 land gets no cultivation after the sowing of the seed, the process 

 of nitrification, which depends very much upon the aeration and 

 stirring of the soil, is comparatively slow after the first great 

 production of nitrates when the land is broken up in autumn. 

 Hence, if there is much washing out of nitrates from the soil in 

 -winter, the wheat crop, more than any other, will suffer, for in its 

 ■case there will be little opportunity of repairing damages. The 

 third column in Table I. shows the enormous losses of nitrates 

 which the soil suffered during the winter of 1903 as far as they 

 can be measured from the nitrates determined in the Rothamsted 

 ■gauge, where the water percolates through sixty inches of soil. 

 As the soil in question has not been manured for the last thirty-five 

 years, and has always been losing nitrates year by year, it is in a 

 highly impoverished condition, so that its production of nitrates 

 will be much smaller than that of a piece of land in ordinary 

 : good heart. Yet this unmanured piece lost nitrates equiva- 

 lent to 130 lb. of nitrate of soda per acre in the five months 

 October, 1903, to February, 1904, as compared with 61 lb. up 

 to a corresponding date this winter. 



The bad wheat crop of 1904 could then have easily been 

 predicted in January last, and could have been foreseen with 

 certainty at the end of February. Both causes of a small crop 

 had been operating together : a late seeding and a saturated 

 soil involved a poor root development, and the great percola- 

 tion had washed away most of the nitrates which were the 

 only source of nitrogen available for the crop. The present 

 •season offers the greatest possible contrast : the early harvest, 

 the well-ripened seed, the dry October and November, gave the 

 plant an early and a vigorous development, so that it had no 

 doubt already assimilated much of the available nitrate before 

 the December rains became heavy enough to cause any washing 

 of salts through the soil. It is, of course, impossible to predict 

 .a heavy crop — there are many possibilities of disaster - between 

 now and harvest — but we can say that a good beginning has 

 been made, and that, granted fairly normal conditions during 

 the next six months, we may safely expect a good crop of 

 -wheat. But, as said before, the negative side is stronger than the 



