BARLEY 



31 



short of that on Plot 7, where minerals are used every year with the same 

 amount of ammonium-salts, thus showing that the previous mineral 

 manuring is carried forward and has an effect in seasons beyond the year 

 of its application. 



HOOS FIELD— BAELEY 



The experiments on the continuous growth of barley were begun in 

 the Hoos field in 1852. The arrangement of the plots and the manures 

 applied to each plot have practically been unchanged since, so that the 

 plots to-day show the effects of more than fifty years' continuous growth of 

 barley under the same treatment year after year. There are four longi- 

 tudinal strips receiving different combinations of the mineral manures; 

 these are all crossed by four breadths receiving different nitrogenous 

 manures. The mineral manuring on the strips is as follows : — (1) None ; 

 (2) Phosphoric acid only, no potash or alkali salts ; (3) Potash, magnesia, 

 and soda, no phosphoric acid ; and (4) Complete mineral manure, supplying 

 both phosphoric acid and the alkaline salts. Each of these is combined 

 with the four cross-dressings of nitrogenous manures — Series O, no nitrogen ; 

 Series A, ammonium-salts ; Series N, nitrate of soda ; and Series C, rape 

 cake. There are other plots, one of which has received farmyard manure 

 for the first twenty years, but has since been unmanured. 



Table XV. — Experiments on Barley^ Hoos Field. Manuring of the Plots 

 per acre per annum^ 1852 and since. 



