October, '22] 



HAYES: SORGHUM INSECTS 



349 



(about 7p. M. to7A. M.) Experiments with which rain interfered 

 are not recorded. Table III gives the results of the experiments. 



Table III 



It will be seen from table III that the exclusion of dew from the poison- 

 ed plant had no effect upon the rate of mortality. The percent killed 

 during the period recorded is so near alike in the two, that the difference 

 is probably due to chance variation. Also by comparing the covered 

 and uncovered checks it will be seen that covering had no effect over the 

 mortality. 



Conclusions 



So considering the results discussed here and those obtained by other 

 investigators, it seems that it has been conclusively shown that the 

 cotton-boll weevil is poisoned by ingestion of poison with its food rather 

 than by drinking the poisoned dew. This conclusion has nothing to do 

 with the time of day when the poison should be applied, for it is a well 

 established fact that better results can be obtained from applying 

 poison while the plant is wet with dew. 



OBSERVATIONS ON INSECTS ATTACKING SORGHUMS 



By Wm. p. Hayes, Assistant Entomolgist 

 Kansas Agricultural Experiment Station'^ 



The following observations were made during the past few years In 

 connection with a study at this station of insects attacking sorghums. 

 The sorghum crop in Kansas is on the whole remarkably free from 

 insect pests, escaping almost entirely the ravages of the sorghum midge 

 and stalk-borers common in southern regions. In the selection of forage 

 crops in western Kansas, consideration must be given to possible injury 

 by grasshoppers and chinch bugs. Sudan grass and milo are much 



^Contribution from the Entomological Laboratory, Kansas State Agricultural 

 College, No. 71. This paper embodies the results of some of the investigations 

 undertaken by the writer in the prosecution of project No. 92 of the Kansas Agri- 

 cultural Experiment Station. 



