212 SOUTHERN FIELD CROPS 



are still in the field; and later 

 generations develop in the crib. 

 Early varieties and those with soft 

 grains are most susceptible to in- 

 jury (Fig. 105). Late planting of 

 medium or late varieties escapes 

 injury, or reduces the number of 

 weevils finding access to the ears 

 in the field. Doubtless much can 

 be done to lessen the weevil injury 

 by selecting corn with a view to 

 weevil resistance. The qualities 

 tending to decrease the number of 

 weevil, but not entirely to avoid 

 them, are (1) a shuck that fits 

 tightly over the end of the ear and 

 (2) a grain that is quite hard. Any 

 means that decrease the number 

 of corn ear- worms would indirectly 

 reduce the injury from weevils, 

 which often enter the ear through 

 the openings made by the former. 

 However, the chief reliance must 

 be on fumigating the stored grain 

 with the vapors made by carbon 

 disulfide. This liquid readily 

 evaporates, or changes from a 

 liquid to a gaseous form. This 

 implies the necessity for tight 



FIG. 105. -AN EAR OF CORN crib Qr f other means o f tr eat- 

 INJURED BY WEEVILS. . . 



(W. E. Hinds.) ing the grain in tight compart- 



