156 



The Rothamsted Grass Experiments. 



receive the same mixed mineral manure, and plot 8 the same, 

 excluding the sulphate of potash, but with an increased 

 amount of sulphate of soda. The results are given in Table 

 XXXVI. 



TABLE XXXVI. AVERAGE PER ACRE PER ANNUM, BY MIXED MINERAL 

 MANURE, WITH AND WITHOUT POTASH ; PLOTS 7 AND 8. 



Average per Acre per Annum. 



There is an average of rather more hay, and of rather more 

 nitrogen and mineral matter taken up, on plot 8 than on 

 plot 7, during the first six years. Whether this arose from 

 the action of the sawdust is uncertain, but the increased 

 amount of nitrogen taken up corresponded very closely with 

 that contained in the sawdust. It has already been observed 

 that sawdust alone gave no increase. 



During the next fourteen years the relations are entirely 



