10 The Bulletin 



and li/o per cent of potash. The fertilization for cotton was on a basis 

 of 400 pounds per acre of a mixture containing 7 per cent available 

 phosphoric acid, 21/2 per cent nitrogen and 21/2 per cent potash. 



Field B. — These plats were used for fertilizer experiments with com 

 in 1906 and 1908 and for fertilizer experiments with cotton in 1905- 

 07-09. 



"Old" Field. — These plats were used for fertilizer experiments with 

 com during 1903 and 1904, Cotton was not grown on this as on Fields 

 A and B. 



Preparation and Cultivation. 



The land in all cases was well prepared by breaking with a two-horse 

 turning plow in the winter, usually in January or February to a depth 

 of 8 or 10 inches, and allowed to remain in this condition until just 

 before planting. It was then cut up thoroughly with a disk harrow. 

 The rows were run off 4 feet apart, the fertilizer distributed in the drill 

 and covered to a slight ridge, usually with one furrow of a disk or other 

 cultivator. This operation took place some time prior to planting, so 

 as to give the ground time to settle somewhat before planting. Cocke's 

 Prolific was the variety of com used in planting all experiments. It 

 was usually planted as soon in the spring as the weather would permit. 

 The planting being done on a slight ridge made by covering the ferti- 

 lizer, but which was usually brought to a level, or almost to a level, by 

 the corn planter. The corn was well cultivated with weeders, harrows, 

 single and two-horse cultivators, requiring not exceeding two furrows to 

 the row for the same cultivation, making the cultivations deep at the 

 beginning and shallow toward the close of the season, when root de- 

 velopment of the plants was well extended through the soil. The culti- 

 vation was repeated each ten days to two weeks during the season, the 

 crop being laid by July 15 to August 1, according to season. The crop 

 was thinned as nearly as possible to one stalk in the hill, every 30 

 inches. 



Fertilization and Fertilizer Materials Used. 



As already stated, the fertilizer was applied in the drill just before 

 planting the com. the exact quantity of material for each row being 

 weighed out separately so that each row would get its proper amount of 

 the several fertilizer constituents. Acid phosphate was used as the 

 source of phosphoric acid ; dried blood as the source of nitrogen (except 

 where there was a comparison of different nitrogen furnishing materials, 

 or where nitrate of soda was used as a part of the nitrogen), manure salt 

 as the source of potash, and rock or building lime for lime. The fer- 

 tilizer materials were analyzed each year and application made on the 

 basis of actual analyses, so as to give the exact quantities of nitrogen, 

 phosphoric acid, and potash required for each plat. For the sake of 

 simplicity and convenience in presenting the results of a number of 

 years' experiments, the fertilizer applications are expressed in terms of 



