1904.] PUBLIC DOCUMENT — No. 33. 121 



tion of the soil as a result of the heavy yield of cabbages 

 last year on the plot receiving the sulfate of potash may in 

 part account for the fact that the sulfate of potash this year 

 fails to show its usual superiority. 



2. Potatoes (^Sulfate v. Muriate of Potash) . 

 The potatoes in this experiment were of the Beauty of 

 Hebron variety ; the seed was grown in northern Maine. 

 This crop occupied two plots (11 and 12), which last year 

 produced a mixed crop of timothy and clover. The sod was 

 broken this spring, and the seed, which had been previously 

 treated with formalin for destruction of scab spores, and 

 budded, was planted on May 16. An effort was made to 

 protect the crop from insects and blight by the use of pre- 

 pared insecticides and fungicides offered in our markets. 

 These proved fairly satisfactory in the destruction of the 

 potato beetle, but were not entirely effective in preventing 

 blight. The vines began to show signs of blight on July 18, 

 but its progress was slow ; there was but very little rot, and 

 the yield was fairly satisfactory. The potatoes were dug 

 after the vines were entirely dead, and the yields were as 

 shown below. 



Muriate v. High-grade Sulfate of Potash. — Potatoes, Yield jicr Acre 



(Brishels). 



Fertilizers used. 



Merchantable. 



Small. 



Muriate of potash, 

 Sulfate of potash, . 



171.71 

 194.58 



29.94 

 29.09 



It will be noticed that the yield of small tubers was practi- 

 cally identical on the two potash salts, but that the sulfate of 

 potash gave a yield of merchantable tubers at the rate of nearly 

 23 bushels per acre gi-eater than the muriate. This result is 

 in exact agreement with the results of many other experi- 

 ments which have been ' tried upon our grounds ; and it 

 seems to be impossible to doubt that sulfate of potash should 

 be generally selected for the potato, rather than the muriate, 

 for all soils which have a fair capacity to retain moisture. 



