May, 1938] Experiments With Grass Hay 5 



of grass hay when used with manure. It was pointed out in the previ- 

 ous report that tlie increase from phosphorus where it was used alone 

 came largely during the first harvest, apparently due to stimulation of 

 germination and early growth after the crop was seeded. 



Each ton of limestone applied at the beginning of the test returned 

 1,547 pounds of hay used at the rate of two tons per acre, but the re- 

 turns per ton at the four-ton rate were only 991 pounds of hay. 



Manure returned 342 pounds of cured hay per acre for each ton ap- 

 plied. Manure was used on certain plots at the rate of 10 tons per acre. 

 Potash was not introduced as a variable in the test. 



A portion of the field on which the experiment referred to was con- 

 ducted was reseeded in 1934 to grass hay. Prior to reseeding, the land 

 had grown a crop of oats and one of red clover and had received three 

 applications of 300 pounds of 8-16-16 fertilizer per acre spread uniform- 

 ly over the land, one of which was applied directly for the seeding. Uni- 

 form applications were made to iron out anj' differences in stand that 

 might result if variables were used. 



Top-dressing was instituted in 1935 with variables which have been 

 applied annually since that date. The plan of the experiment was 

 changed to include potash and the increment of nitrogen was doubled 

 from the previous work. 



The rates of fertilization in the revised experiment were as follows: 



Rate Per Acre Material Used 



32 lbs. nitrogen from 200 lbs. nitrate of soda 16 % N 



32 lbs. phos. acid from 200 lbs. superphosphate 16% or 



160 lbs. superphosphate 20% 

 32 lbs. potash fi'om 64 lbs. 50% muriate of potash or 



53.33 lbs. 60% muriate of potash 



This is equal to a 1-1-1 fertilizer ratio and the amount applied was 

 equivalent to 400 pounds of an 8-8-8 fertilizer where the complete fer- 

 tilizer was used, to 400 pounds of an 8-0-0 where nitrogen only was ap- 

 plied and to the same amount of an 0-8-8 on the plots receiving phos- 

 phoric acid and potash only. 



"With the exception of twelve plots of the thirty-nine comprising the 

 experiment, no manure has been used on the land for a long time, twenty 

 years at least. The twelve plots in question received a 10-ton applica- 

 tion of manure in 1925. Tlie field is divided into three strips of thir- 

 teen plots each and four of the manure plots are located in each strip. 



Lime was applied to one of these strips in 1925 at the rate of four 

 tons per acre and to another at the rate of two tons per acre, while the 

 third strip has never been limed. These strips are covered by an equal 

 number of plots of each top-dressing treatment. 



The soil of this field is not high in organic matter and hay yields are 

 somewhat dependent upon spring rainfall. Grass hay is responsive to 

 fertilizer treatments on this field as the following three-year summary 

 shows : 



