Summary of Twenty Years' Results. 117 



SUMMARY OF THE RESULTS OF TWENTY YEARS' 

 EXPERIMENTS ON THE CONTINUOUS GROWTH 

 OF BARLEY UPON THE SAME LAND. 



It remains now to draw such general conclusions as seem 

 warrantable from the results of the experiments on the con- 

 tinuous growth of barley on the same land, and to show the 

 practical bearings of the results. The barley field imme- 

 diately adjoins that devoted to the experiments on wheat, 

 and has a soil and subsoil of similar general character, and 

 described as a somewhat heavy loam, with a subsoil of raw 

 yellowish-red clay, but resting in its turn upon chalk, which 

 provides good natural drainage. Though, in wet seasons, 

 such a soil is not well suited for the growth of the crop after 

 roots fed on the land by sheep, as is the custom of the 

 locality, yet the recorded results abundantly prove that, 

 when grown under favourable conditions, large crops of 

 barley, of good quality, may be obtained from such land. 

 Without manure, the average produce over twenty years 

 was 21 bushels of dressed barley grain, of 5 2 Jib. per bushel, 

 and 12cwt. of straw. Though the quantity fell off con- 

 siderably, the quality was considerably higher over the 

 second than over the first ten years. Compared with wheat 

 without manure, barley gave more grain, less straw, but 

 nearly the same quantity of total produce. It, however, 

 fell off more in produce of grain, and about equally in straw, 

 over the later years. By farmyard manure, the average 

 annual produce was more than 48 bushels of dressed grain, 

 of 54|lb. per bushel, and 28cwt. of straw. The quantity 

 of both grain and straw, and the quality of the grain, 

 were considerably higher over the second than over the 

 first ten years. As without manure, so with farmyard 

 manure, barley, compared with wheat, yielded more grain, 

 less straw, but much about the same quantity of total 

 produce. Mineral manures alone gave very poor crops, 



