232 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 8 



Spring and Summer Precipitation and Midge Injitrt 





1913 



1914 



Station 



Rainfall, May, June 

 and July, Inches 



Damage by 

 Midge 



Rainfall, May, 

 June Siiid July 

 Inches 



Damage by 

 Midge 



Beaumont 



9.66 



20% 



32.64 



100% 



College Station 



4.03 



40% 



9.45 



95% 





5.02 



None 



16.02 



50% 





8.44 



15% 



4.77 



50% 



Beeville 



5.45 



None 



12.62 



50% 





As pointed out by Dean,^ the only remedial measures thus far evi- 

 dent consist in clean harvesting, the complete destruction of Johnson 

 grass and possibly the fumigation of seed to kill the hibernating larvae. 

 Johnson grass is a favorite host plant of the midge, its seed heads 

 afford protection to the midge larvae and its early heading in the 

 spring gives opportunity for a generation of midges to be produced in 

 advance of the heading of cultivated crops. 



Sudan grass, in the latitude of central Texas, would produce two and 

 sometimes three, seed crops per season were it not for the midge, but 

 in seasons of heavy infestation there only remains the possibility of 

 securing a very late crop of seed at a time when the parasitism of the 

 midge is high. Thus at both College Station and Angleton in 1914, 

 a partial late crop of seed was secured, though earlier crops of the seed 

 were entirely destroyed. 



The Conchuela 



Strangely enough, the area which is too dry for the sorghum midge 

 is the one in which the conchuela, Pentatovia ligata Say, reaches its 

 greatest abundance. While this plant-bug is a general feeder, attack- 

 ing cotton, small grains, alfalfa, foliage of trees, garden vegetables, 

 etc., it is particularly avaricious in its attack on all members of the 

 sorghum family. In Loving County during the past season it even 

 prevented, to a large extent, the seed production of Johnson grass. 

 Thus far large areas of Sudan grass have not been grown in the localities 

 where the conchuela is at present abundant, but, owing to its fondness 

 for all other members of the sorghum family, there seems little doubt 

 that it will prove to be a serious obstacle to the extended cultivation 

 of Sudan grass in the semi-arid sections. 



1 Bui. 85, Part IV, p. 58, Bureau of Entomology. 



