106 Maine Agricultural Experiment Station. 1920. 



fertilizer No. 5549 which, when applied at the rate of 2,000' 

 pounds per acre, was equivalent to an application of 17.6 pounds 

 of anhydrous borax per acre. With this fertilizer the 20 pots 

 were divided into 5 different lots of 4 pots each, according to 

 the method of application. In the first lot the fertilizer was 

 thoroughly mixed with the upper 6 inches of soil in each pot. 

 In the second it was distributed in a strip about 3 inches wide 

 across the pot (in a manner similar to the way it is deposited in 

 the row in the field by the planter) just below the seed-piece, 

 but not in direct contact with it. In the third the fertilizer was- 

 distributed in a manner similar to the second, but just above 

 the seed-piece. In the fourth lot it was thoroughly mixed with 

 the 3 inches of soil just below the seed-piece, while in the fifth 

 it was thoroughly mixed with the 3 inches of soil above the 

 seed-piece. 



With each of the remaining 5 fertilizers, namely, Nos. 5389, 

 5518, 5536, 5513 and 5409, only 4 pots were used, representing. 

 two pots each of the second and third methods of application 

 described for No. 5549. Four other pots were planted with 

 potatoes without adding any fertilizer. These and those in 

 which fertilizer No. 5409 was used, which contained no borax, 

 were introduced as checks. 



Seed tubers used. There were available a small amount of 

 tubers which had been produced in pots in the greenhouse, har- 

 vested in the early summer and stored in a cool basement. These 

 were firm and vigorous and some were just beginning to sprout 

 at the time of planting. A half of a tuber was placed in each 

 pot, care being taken to distribute the halves so that no two 

 would have the same fertilizer treatment. 



Depth of planting. In all cases the distance was 3 inches 

 from the top of the seed-piece to the top of the soil after plant- 

 ing. Wherever the fertilizer was distributed in drills above or 

 below the seed-piece without mixing with the soil, a thin layer 

 of soil was placed between it and the seed-piece. 



Watering. All of the pots which were 10-inch and of the 

 ordinary unglazed type, were placed on benches with saucers 

 underneath. One-half of all of the pots, representing the dif- 

 ferent methods of application of the various fertilizers, were 

 kept heavily watered, while the other half had a scanty water 

 supply or were kept as dry as possible and still have them moist 

 enough for growth. As a rule this required about 300 and 150 



