August, 1911.] 



145 



Scientific Agriculture. 



poor condition, and more than usually 

 short of organic matter, because it had 

 been farmed for several years without 

 any farmyard manure. No fertilisers 

 were applied, but during 1904, 1905, and 

 1900, on the four plots rape, crimson 

 clover, vetches, and mustard were sown, 

 and turned in at the end of the summer. 

 The treatment was repeated because 



the land was in such poor condition that 

 none of the crops were large, the 

 vetches and mustard growing better 

 than either the crimson clover or the 

 rape. A crop of wheat was taken in 

 1907, after which, in 1908 and 1909, the 

 green crops were repeated, a second 

 crop of wheat being taken in 1910. The 

 following table gives the results for the 

 two crops of wheat : — 



Table I. —Yield op Wheat Per Acre after Green Manuring. 

 Little Hoos Field, Rothamsted. 



Previous Green Crop. 



Dressed 

 Grain. 



Dressed 

 Grain. 



Offal 

 Grain. 



Total 

 Grain. 



Straw. 





Bushels. 



Lb. 



Lb. 



Lb. 



Cwt. 



1907. After Mustard 



29-9 



1,923 



96 



2,019 



22-5 



1907. „ Rape 



21'3 



1,376 



75 



1,451 



29-6 



1907. ., Crimson Clover.. 



325 



2,096 



294 



2,390 



36-1 



1907. ,. Vetches 



39-7 



2,542 



210 



2,752 



39-4 



1910. After Mustard 

 1910. ,, Rape 

 1910. „ Crimson Clover.. 

 1910. ,, Vetches 



19 -6 



20-8 

 30-8 

 34-4 



1,247 

 1,327 

 1,926 

 2,144 



34 

 37 

 85 

 127 



1,281 

 1,364 

 2,011 

 2,271 



15- 3 



16- 3 

 27 

 34-7 



From these figures it will be clear, as, 

 indeed, it was to the eye, that the superi- 

 ority of the wheat after the leguminous 

 crops of crimson clover, and particularly 

 of vetches, is beyond any possible limit 

 of experimental error. During the last 

 year the value of the previous growth 

 of vetches was particularly manifest, as 

 the wheat on this plot possessed a fine 

 colour, very free from blight, and 

 yielded more than any of the manured 

 wheat plots on the experimental ground. 

 A plot on the same field, where the 

 wheat had been manured with cake-fed 

 dung after the preceding crop of barley, 



only yielded 20*1 bushels ; indeed, all 

 the manured plots in this field gave 

 very poor results. 



The following determinations of the 

 percentages of nitrogen in the grain and 

 straw would indicate that the superior- 

 ity in the yield of the plots on which the 

 vetches and crimson clover had been 

 grown was due to the greater amount 

 of nitrogen there available in the soil, 

 but the general superiority of these 

 plots over the wheat elsewhere must be 

 set down to the better condition of the 

 soil brought about by the accumulation 

 of organic matter. 



Table //.—Quality of Wheat Grown after Green Manuring. 



Previous Green Crop. 



Weight 

 per bushel. 



Nitrogen 

 in Grain. 



Nitrogen 

 in Straw, 



Ratio of 

 Grain to 

 Straw =100. 



Ratio of 

 Offal to 

 Dressed 

 Grain = 100. 





Lb. 



Per cent. 



Per cent. 







1907. After Mustard 



64-3 



2-065 



0-276 



59-9 



5-0 



1907. „ Rape 



64-7 



2'088 



0-267 



56-5 



5-4 



1907. ,, Crimson Clover 



64-5 



2-217 



0-320 



58-0 



14 



1907. „ Vetches 



64-0 



2-386 



441 



61-3 



8-2 



1910. After Mustard 

 1910. „ Rape 

 1910. ,, Crimson Clover 

 1910. „ Vetches 



63'5 

 63 -8 

 62-7 

 624 



1-849 

 1-852 

 1-888 

 1-953 



0-3162 

 0-3054 

 0-3756 

 0-3595 



74-8 

 74-6 

 66-4 

 58-4 



2-7 

 2-8 



4- 4 



5- 9 



19 



