210 THE EOTHAMSTED EXPEEIMENTS. 



that on ordinary arable land where clover had entirely failed, 

 some other Leguininosse, having more extended root range, or 

 more powerful root habit, grew luxuriantly, and yielded large 

 crops, containing large amounts of nitrogen, for a number of 

 years in succession. Lastly, in another field, where beans had 

 frequently failed, red clover was afterwards sown, and gave 

 unusually large crops. 



Eeferring to the results in Table 58, it is seen that when 

 clover was grown in 1850, that is in the first course, and when 

 it had not been grown on the same land for many years, large 

 crops were obtained on all the plots ; though the larger where 

 the mixed manure including potash, and also nitrogen, had 

 been applied for the root-crop three years previously. For 

 the second, third, and fourth courses, clover was sown with 

 the preceding barley, but in all three it failed in the winter, 

 and beans were grown instead ; that is, in 1854, 1858, and 

 1862. After these repeated failures, clover was not sown for 

 the fifth and sixth courses, but beans were taken instead, in 

 1866 and in 1870. In the seventh course, clover was sown 

 again, with the barley, and gave three cuttings in 1874; that 

 Effects of is, twenty-four years since the last good crop. Without 

 lHoveTand manure > the produce was, however, not much more than one 

 beans. ton per acre ; with superphosphate it was much more ; and 

 with the mixed manure, including potash, much more still — 

 corresponding to about 3| tons of clover hay. For the eighth 

 course clover was not sown, but beans were taken in 1878. 

 For the ninth and tenth courses, however, clover was again 

 sown, yielding in the ninth (1882) even more than in 1874; 

 but in the tenth (1886) very much smaller crops, though more 

 with mineral manure alone, now including potash, than with 

 the mixed manure containing nitrogen also. Lastly, for the 

 eleventh course, clover was again sown with the barley, but 

 failed, and in 1890 beans were grown instead ; the crops, as 

 in the case of the clover in the tenth course, being greater 

 with mineral manure alone (now including potash) than with 

 the mixed manure containing nitrogen also. 

 Failures of Thus, in only four out of the eleven years in which clover 

 clover. should have been grown, was any crop obtained, and beans 

 had to be taken in the other seven. The produce of clover is 

 given in the lower division of the table, side by side with the 

 total produce (corn and straw) of the beans; and the results 

 for the clover are entered in parentheses. 

 Summary Briefly to summarise the results given in the table, it may 

 dwwandf De stated that the average produce of clover, reckoned as hay, 

 beans. was, without manure, rather over 3000 lb. ; with the super- 

 phosphate (in the last year with potash, soda, and magnesia 

 also) nearly 6000 lb. ; and with the mineral and nitrogenous 



