MANURES AND FERTILIZERS. 63 
on the lighter soils of the State, fertilizers con- 
taining a large proportion of potash are needed 
to give the best results,” while fertilizers with 
relatively large proportions of phosphoric acid 
produce the best results on heavy, clayey soils.* 
At the Massachusetts State experiment sta- 
tion for some years a series of 10 plats of one- 
tenth acre each in size have been grown to 
corn and treated with one or two special arti- 
cles of plant food, or else left unmanured. In 
1888 those plats receiving a dressing in which 
potash was the dominant ingredient gave ma- 
terlally increased yields of grain over the nitro- 
gen plats, though a combination of 97 Ibs. of 
sulphate of potash and magnesia and 100 Ibs. 
of dissolved boneblack gave the best yield. 
In experiments conducted over the State of 
Massachusetts in 10 different counties, by Prof. 
W. P. Brooks of the agricultural college, while 
it was shown that soils differ widely in their 
requirements, it was also demonstrated that 
potash more often proves beneficial or much 
more largely beneficial than either nitrogen or 
phosphoric acid.; Potash as arule most largely 
increases the yield of both grain and stover, 
but its effect upon stover production is greater 
than upon grain production. 
* Storrs’ agricultural experiment station. Report of 1892, 
p. 67. 
{ Experiment Station Record, III, p. 165. 
