8 SOME CONDITIONS INFLUENCING THE YIELD OF HOPS. 



the second group. If through better methods of handling and closer 

 attention to the details of culture the number of hills in the first 

 group can be materially diminished, the average yield for the entire 

 acre will be correspondingly advanced toward the upper limit of 

 yield in the second group, and the total yield thereby substantially 

 increased. In the following pages some suggestions will be given as 

 to how this may be accomplished. 



RELATION OF NUMBER OF VINES PER HILL TO YIELD. 



The records obtained from the acre under observation show, fur- 

 ther, that the number of vines trained from the individual hills 

 varied from one to eight. The distribution of the hills according to 

 the number of vines is shown in the following: 



Hills having one vine 54 



Hills having two vines 113 



Hills having three vines 135 



Hills having four vines 186 



Hills having five vines 188 



Hills having six vines 168 



Hills having seven vines 8 



Hills having eight vines 1 



Total 853 



Several explanations of the variation in vines to the hill may be 

 advanced. Among them are the recent replanting of certain hills, 

 in which case they would not have the vigor of older hills; the weak- 

 ening of the roots of some hills by disease or the attacks of insects; 

 the exhaustion of the vigor of others through long-continued pro- 

 duction ; the breaking off of a portion of the vines in cultivation ; the 

 destruction of some vines by the wind ; or the cutting off of too many 

 vines at the time of training. What seems most probable is that 

 through the carelessness and negligence of the workmen the proper 

 number of vines was not trained. It is probable, also, that indi- 

 vidual differences in vigor and productiveness should be taken into 

 account. 



The relation between the number of vines per hill and the yield 

 per hill is shown in Table III. 



[Cir. 561 



