Barn and Field Experiments in 1917. 23 



For the 1-40 acre plots these amounts are divided by 40. 

 These amounts are further reduced for application to oats by- 

 dividing by 120 and for application to grass by dividing by 240. 



It was also desired to compare the usual potato formulas 

 of 5-8-7 and 3-8-10 goods, insoluble phosphate rock in the form 

 of finely ground floats with acid phosphate, and nitrogen in 

 the form of dried blood and in tankage with the mineral nitrogen 

 used in the soil test. These 5 additional plots with 6 check 

 plots increase the number of plots to 32. 



FIELD ARRANGEMENT OF PLOTS. 



It was thought that to overcome lack of uniformity in soil 

 each plot should be in triplicate. This makes a total of 96 plots. 

 As potatoes are the important cash crop of Aroostook County 

 it seemed important that potatoes should be grown annually. 

 As it was prohibitive to increase the number of plots much 

 above 100 because of the cost of caring for a larger number, 

 it was decided to grow the plots in a 3 year rotation of potatoes, 

 oats and clover. This plan not only gives a potato crop each 

 year but it makes the experiment better in that the effects of 

 unfavorable weather conditions of any single year are minimized. 

 The field selected for the location of the plots contains about 

 5 acres. It is isolated from the other cultivated fields on the 

 farm. It has a gentle slope toward the west. 



The plots are in 3 series : A, consisting of 33 plots, one 

 extra check plot being added to this series, B, 32 plots and C, 

 32 plots. The several plots in each series are separated by 

 pathways 33 inches wide running lengthwise and 36 inches 

 wide running crosswise, while the different series are separated 

 by roadways 6 feet in width, running lengthwise. The arrange- 

 ment of the plots in the field is shown in Figure 3 on page 24. 



For convenience of reference the plots are numbered by 

 row and by plot. Thus Plot 11 is the first plot in the first row, 

 while plot 36 is the sixth plot in the third row. 



Outline of the Experiment in 1917. 



The field was in potatoes in 1914 and fertilizer was used 

 at the rate of 1500 pounds per acre of a 5-8-7 fertilizer. In 

 191 5, it was seeded to timothy and oats. 



