lane, 1940] Experiments \\'itii Potatoes 15 



which has been summarized by Ciimmings and Houghland (11) who state 

 that the fertilizer should be accurately placed in the soil with respect to 

 the seed piece to be of greatest benefit to the potato crop, and that changing 

 the position only two inches in some instances either decreased or in- 

 creased yields appreciably. Practically all of the experimental work has 

 compared different methods of placement, but has not compared placement 

 with actual broadcasting as do the results recorded here. 



From the farmer's angle, the problem is to deliver the fertihzer into 

 the soil far enough away from the seed pieces so as not to cause burning, 

 and still near enough so that the maximum benefit will be derived from the 

 application. If that were always done by planter application, there would 

 be no need for other methods. However, planter application, especially by 

 tilder machines, is not always perfect; hence, there is still need for other 

 means of application. Broadcasting is one method that can be employed, 

 and one that is certain not to cause fertilizer burn. 



Residual Fertilizer and Lime Effects 



All of the fertilizer was applied to the potato crop in the rotations 

 studied. Oats and hay have been harvested and yield-records taken to 

 see what residual effect, if any, resulted from the use of fertilizer variables 

 on the potato crop. 



Average yields of oat-hay for the first period are given in Table XIV. 



TABLE XIV. Yields of Jackson farm oats in pounds of cured hay 



per acre, 1928-1932. 



While there are ncj differences in this table that are statistically sig- 

 nificant, it is interesting to note that whenever an element was decreased or 

 omitted, or a plant food was reduced, the resulting yield was lower than 

 that of the check plots. Plots receiving an increased application of plant 

 food or lime show an increase in vield, facts which should lend some value 

 to the results. 



