Continuous Growth of Barley. 87 



?!. EXPERIMENTS ON THE CONTINUOUS 

 GROWTH OF BARLEY UPON THE SAME LAND 

 FOR TWENTY YEARS. 



THE first twenty years' experiments 011 the continuous 

 growth of barley extended from 1852 to 1871, and the 

 results are given in the R.A.S. Journal, 1873. The land 

 selected was a portion of that immediately adjoining the 

 experimental wheat field. The wheat field has, however, as 

 a matter of experiment, been artificially drained, whilst the 

 barley field has not. The custom of the locality, in the case 

 of land of similar quality, is to take the barley crop after 

 roots fed off by sheep ; but the soil is too heavy for this to 

 be done with advantage in wet seasons. Nevertheless, good 

 crops, both as regards quantity and quality, are so grown on 

 such land in favourable seasons, and may, as a rule, be relied 

 upon when barley is taken, not after folding, but after 

 another corn crop. The object of the experiments was to 

 obtain answers to such questions as the following : What 

 are the grain-yielding capabilities of such land ? What 

 its powers of endurance ? In what constituents, or class of 

 constituents, does it soonest show signs of exhaustion? 

 And how far will the answers arrived at on these points in 

 reference to it, accord with, or be a guide to, those which 

 would apply to any large proportion of the arable land of 

 Great Britain when farmed in the ordinary way, with 

 rotation ? 



The previous history of the land was : 1847, Swedish 

 turnips, with farmyard manure and superphosphate (the 



