KOTATION OF CHOPS. 223 



of dry matter in the crops of beans, even when grown in 

 rotation, they were much less still when grown continuously. 

 This was the case whether we look to the amounts in the 

 corn, the straw, or the total produce. Indeed, the lines of Effects oj 

 total produce show that the average amounts in the contin- manures - 

 uously grown crops were, under each condition of manuring 

 or other treatment, less than half as much as those grown in 

 rotation. In both cases, there was somewhat more with 

 superphosphate than without manure, and more still with 

 the mixed manure, including both potash and nitrogen, but 

 even under these conditions, and in rotation, the produce was 

 very small. 



Under each condition as to manuring, the produce of dry 

 matter in the clover grown in rotation was more, and in some 

 very much more, than in the beans so grown. Without 

 manure, it averaged only about 1 ton per acre per annum ; 

 with superphosphate, in one case more than 2, and in the 

 other more than 2\ tons ; and with the full manure, including 

 potash and nitrogen, it averaged more than 3 tons. 



Lastly, the average production of dry substance in the six 

 crops of beans and two of clover taken together was — with- 

 out manure only about f ton ; with superphosphate, in one 

 case little more than 1 ton, and in the other rather more than 

 \\ ton ; 'and, with the mixed manure, in both cases less than 

 If ton. These amounts in the leguminous crops with the 

 mixed manure were, however, greater than those obtained in 

 the turnip crops, but less than those in either the barley or 

 the wheat grown in rotation. The significance of the amounts 

 grown in the leguminous crops will, however, be the more 

 clearly recognised when we come to consider the quantities 

 of nitrogen in the different crops ; and also the fact of the 

 large proportion of the manurial constituents of the legumin- 

 ous crops grown in rotation, that will generally be retained 

 on the farm. 



The Dry Matter in the Wheat Crops. — The bottom division 

 of the Table (60) shows the average amounts of dry substance 

 in the wheat — grain, straw, and total produce — grown in 

 rotation, and those obtained in the same years in another 

 field under as far as possible parallel conditions as to manur- 

 ing, but grown continuously — that is, year after year on the 

 same land. 



A glance at the figures shows that, both without manure Less dry 

 and with superphosphate alone, the amount of dry matter ^^uous- 

 produced was, both in grain and straw, in each case consider- than in 

 ably less than half as much in the crops grown continuously rotatior > v 

 as in those grown in rotation ; and that, even with the mixed 

 manure, supplying both mineral constituents and nitrogen, it 



