10 BULLETIN 1418, U. S. DEPARTMENT OF AGRICULTURE 
SUMMARY 
All the tests here cited indicate a marked improvement in the 
growth of alfalfa from applications of acid phosphate. As between 
the 16 per cent and the 44 per cent acid pee there seems to 
be little preference, so far as benefit to the alfalfa is concerned, pro- 
vided equivalent quantities. of phosphoric acid are applied. This 
being the case, it would appear that the farmer should use whichever 
form is the cheaper, based upon the relative proportions of this 
element. 3 
Barnyard manure showed some benefit but not enough to justify 
paying much for it, as the cost of hauling and applying is consider- 
able. 
Neither gypsum nor sulphur had an appreciable effect on the yields 
of alfalfa. 
In preliminary tests plats receiving applications of acid phosphate 
have yielded appreciably more seed than the accompanying checks. 
