New York Agricultural Experiment Station. 29 



On June 29 the crop was cultivated again, using a one-horse iron 

 cultivator in place of the Hudson's cultivator previously used. At 

 this time the vines almost completely covered the ground, except 

 where no fertilizer was used. 



On July 19 the late blight began to make its appearance, owing 

 to the prevalence of extremely wet and warm weather. On July 22 

 Mr. Stewart sprayed the potato-tops thoroughly with Bordeaux 

 mixture. They were cultivated again at this time. On August 1, 

 they were again sprayed. 



On August 20 and 21, the field was cultivated again and the 

 weeds were hoed out. At this time the vines were mostly dead. 

 Wliere they had not been sprayed, they were completely dried up. 



On September 3, the digging of the potatoes commenced. The 

 potatoes were carefully sorted and weighed under the supervision 

 of one of the representatives of the Station. The machine used for 

 sorting the potatoes separated those less than 1|- inches in diameter 

 from the marketable ones. 



We will now consider in order — 



1. The composition of the fertilizers used. 



2. The amount of nitrogen, potash, and phosphoric acid used on 

 different plots. 



3. The relation of the constituents of potato fertilizers to the 

 amount of fertilizing materials removed by the potato crop. 



4. The yield of potatoes. 



5. Relation of yield of potatoes to cost of fertilizers used. 



6. Comparison of results in applying ^fertilizers broadcast and in 

 the row. 



1. The Composition of the Fertilizers Used. 



In the table below we state the composition of the different ferti- 

 lizers used, giving the manufacturer's guarantee and the results of 

 the Station's analysis. We designate the different fertilizer simply 

 by the name of the manufacturer. 



