162 



The Rothamsted Grass Experiments. 



organic matter somewhat in the same condition as they are 

 provided in farmyard manure. Table XXXVIII. shows the 

 results. 



TABLE XXXVIII. AVERAGE PER ACRE PER ANNUM, BY 400LB. AMMONIA- 

 SALTS, WITH MIXED MINERAL MANURE CONTAINING POTASH, AND 

 2000LB. CUT WHEAT STRAW; PLOT 13. 



Average per Acre per Annum. 



There is here considerably more average produce of hay, 

 and more of nitrogen and mineral matter removed, over the 

 twenty years, than by the same manures without the straw. 

 And, instead of a reduction, there is a considerable increase 

 in the yield of hay and of nitrogen, and a nearly equal yield 

 of mineral matter, over the second ten years compared with 

 the first. 



It is not very easy to account for the greater yield where 

 the cut straw was used, i.e., of plot 13 over plot 9. Analyses 



