102 Maine Agricultural Experiment Station. 1920. 



those which might be selected under actual experiment. Two of 

 these will be described by way of illustration. 



Mr. A. on one side of a field of several acres applied a 

 3-6-6 fertilizer at the rate of 1700 pounds per acre, all in the 

 drill at planting time. Next to this, a section of the field was- 

 planted with 1300 pounds of the 3-6-6 goods per acre in the 

 drill, with 500 pounds of a 5-10-0 fertilizer applied later on top 

 of the row. Next came 4 rows with 1700 pounds per acre of 

 5-10-0 applied in the drill at planting time. Then following 

 were two and a fraction rows with 1300 pounds per acre of 

 3-6-6 in the drill at planting time and with 500 pounds of 5-10-0 

 on top of the row, the same as the second section of the field 

 described. The remainder of the field was planted with 5-10-0 

 goods at the rate of 1700 pounds per acre in the drill at plant- 

 ing time. 



When examined first on July 21 the plants where the 5-10-0 

 fertilizer was used alone were, on the average, strong and vig- 

 orous. Where the 3-6-6 fertilizer was used alone or in com- 

 bination with the 5-10-0 goods there appeared, in addition to 

 numerous "skips" or failures to produce plants, the character- 

 istic stunting of the plants, with yellowing of the leaves, more 

 especially at the margins, and varying amounts of injury to the 

 parts below ground. The injury was more pronounced where 

 the 1700 pounds per acre of the 3-6-6 fertilizer was applied in 

 the drill at planting time than where only 1300 pounds of this 

 fertilizer was used at that time and 500 pounds of 5-10-0 'was 

 applied later. 



Figure 16 is from a photograph of the two and a fraction 

 rows which received 1300 pounds per acre of the 3-6-6 in the 

 drill and 500 pounds of the 5-10-0 later. On either side are 

 rows of plants which had 5-10-0 alone at the rate of 1700 pounds 

 per acre in the drill. The barrel stave in one row indicates 

 where one fertilizer gave out and the other began. 



Mr. B. had a field of 44 acres of potatoes, on which he 

 applied a 4-8-4 fertilizer in the drill. He began to plant using 

 this at the rate of 2400 pounds per acre. Later he cut the 

 amount down to 2000 pounds per acre. Then seeing that he had 

 an insufficient amount of fertilizer to finish the piece, and being 

 unable to secure an additional supply, he reduced the amount 

 from time to time till he reached the minimum that the planter 



