MICHIGAN EXPERIMENT STATION BULLETINS. 131 



the present price of potatoes it would be better to feed the small potatoes 

 to stock, for which they are worth at least one fourth as much as corn, and 

 use large potatoes cut so as to plant at the rate of from 12 to 15 bushels per 

 acre. 



If one has a large supply of small potatoes, just under market size, and 

 has no use for them, it would pay, perhaps, to use them for seed; but as 

 advised last year, this practice should not be kept up from year to year, 

 without obtaining a new stock of seed potatoes. 



In the experiments to ascertain the best depth for planting, the results 

 seemed to favor covering the seed about 3 inches. This seems to be 

 correct for dry seasons. 



FERTILIZERS FOR POTATOES. 



The plots used for the experiments with fertilizers contained 4 square 

 rods each, and as these were duplicated with the fertilizers above and 

 below the seed, each fertilizer mixture was tested upon 1-20 of an acre. 



The fertilizers used were stable manure, under and over the seed, 

 and as a mulch between the rows, wood ashes, nitrate of soda, sulphate 

 of ammonia, dissolved bone black, ground bone, muriate of potash and 

 sulphate of potash, each alone, and in various combinations, besides 

 Odorless (Iron) Phosphate, Bone and Potash and Homestead Super- 

 phosphate, of the commercial mixtures. 



The manure was applied at the rate of 20 loads (10 cords) per acre; 

 the ashes at the rate of 40 bushels; sulphate of ammonia at the rate 

 of 160 lbs.; nitrate of soda, 240 lbs.; muriate and sulphate of potash. 

 240 lbs., and ground bone and dissolved bone black, 400 lbs. The highest 

 application to any one plot consisted of a mixture of 240 lbs. muriate of 

 potash, 240 lbs. nitrate of soda, and 400 lbs. ground bone at an expense of 

 $16.00 to $18.00 per acre. The least expensive fertilizer was 240 lbs. of 

 sulphate of potash, at a cost of $3.50. 



Four varieties were used in the test in each plot, but by an error in 

 selecting the seed, only two of these were the same throughout, and 

 «xact comparisons can not be made except of the yields of these varieties. 

 The following tables show the yield of each variety, and the average 

 yield obtained from the use of the different fertilizers. 



