16 



U. OF N. H. AGR. EXPERIMENT STATION [Bulletin 227 



28. This year no manure was used; in previous years twenty 

 spreader loads have been applied. 



Table V indicates the yields per acre for each of the several treat- 

 ments during the five years of the test. 



Table V — Yields of potatoes per acre on plots treated with varying amounts of potash 



The fertilizer was applied at the rate of 1200 lbs. per acre of a 

 4-8-0 grade plus enough nuiriate of potash to make the 3, 6, and 10 

 per cents. For the first four years the plots were one-quarter acre in 

 size; in 1926 they were cut to 9 x 20 and were run in duplicate. While 

 the results of these tests are not consistent in every respect, they seem 

 to indicate that where stable manure is used in medium applications, 

 the supplementary fertilizer need not contain more than 4 to 6 per 

 cent of potash. 



Fertilizer Placement Tests on Potatoes — [Hatch Fund) 



In order to secure some data on the effects of different distribu- 

 tions of the fertilizer on the yield of potatoes, four different methods 

 of application were used on duplicate plots. The seed pieces were cut 

 uniformly to two eyes per piece and were planted one foot apart in 

 the row. The potatoes were planted May 21 and harvested September 

 30. The average yields per acre with each method of application are 

 shown in the following table: 



Fertilizer above the seed 212 6 bus. 



Fertilizer below the seed 214 6 bus. 



Fertilizer at side of seed 225 . 7 bus. 



Fertilizer with the seed 229 . 7 bus. 



The mixture of fertilizer used was a 4-8-4 grade and was api)lied at 

 the rate of 1800 lbs. per acre. No striking results were secured. 



The Value of Manure for Potatoes — (Hatch Fund) 



The question is frequently asked: What is a ton of manure worth, 

 or, how valuable is manure for this crop or for that? In order to get 

 some figures on this question as it affects potatoes, plots were planted 

 in dui)Iicate with "no fertilizer", with 12 tons of manure per acre and 

 with 24 tons per acre. The manure used was partially rotted and was 

 harrowed in just before planting. The yields per acre were as fol- 

 lows: 



