248 



Journal of Agricultural Research 



Vol. IV, No. 3 



Several points of interest which do not show in Table VIII were espe- 

 cially noticeable at Edgar. There, as at Huntley and Bozeman, the 

 irrigation water was not always distributed evenly over the plots, and 

 some of the higher spots generally remained fairly dry, even in the plots 

 that were supposed to be the wettest. When the beets were pulled, such 

 areas were noticeably the most heavily infested. Had it been possible 

 to soak thoroughly all of the surface soil in the wet plots at each irriga- 

 tion, the infestation in such plots would have been in all probability still 

 further reduced. 



One of the wet plots was adjacent to an irrigating ditch which carried 

 more or less water all summer. Moisture seeped from the ditch into the 

 beet field, and at the time the beets were pulled the soil in the first and 

 second rows from the ditch was noticeably more moist than in the 

 remainder of the plot. It is highly significant that each of these rows 

 contained more plants entirely free from root lice than did any of the other 

 78 rows included in the Edgar experiment. The infestation in the first 

 six rows from the ditch is given in Table IX. 



Table IX. — Relative root-louse infestation in six rows of sugar beets close to an irrigation 



ditch at Edgar, Mont. 



SUMMARY OF FIELD EXPERIMENTS 



In summing up the results of the irrigation experiments at Huntley, 

 Bozeman, and Edgar, it may be said that sugar beets grown under rather 

 moist conditions were the least infested with root lice and yielded the 

 highest both in sugar content and in tonnage. By combining the results 

 from the three experiments Table X has been constructed. 



