Circular No. 166. 



Issued January 30, 1913. 



United States Department of Agriculture, 



BUREAU OF ENTOMOLOGY. 

 L. O. HOWARD, Entomologist and Chief of Bureau. 



FLOUR PASTE AS A COMROL FOR RED SPIDERS AND 

 AS A SPREADER FOR CONTACT INSECTICIDES. 



By AViLLiAM 15. Parker, 



Ent<iiiiol<i</i(<il Assistant. 



RESULTS OF F.XI'EROIENTS. 



During some spra^'ino- experiments for the control of the red spider 

 {Tetrdiii/cJnis hhnariihifus Harv.) on hops in 101-2 some diflicukv Avas 



Pig. 1. — Llmc-sulphur mixture and flour paste rl(>ft half I, sliowing spreadiiiy: effect of 

 flour paste; lime-sulphur mixture straijrlit ( rii;;ht half), showing beaded etTeet due to 

 lack of flour paste. (Orifiinal.) 



experienced in obtaining an effective spreader for the lime-sulphur 

 solutions, due to the fact that soap forms a precipitate -with the cal- 

 cium polysulphid. While testing the following combination — flow- 



1 



