Cooperative Spraying Experimients. 171' 



A natural enemy of the grape root-worm. — While examining a vine for eggs 

 of the root-worm in a vineyard near Ripley in July, 1905, I noticed that the eggs 

 in several of the clusters were darker colored than usual. Closer examination re- 

 vealed a minute parasitic fly developing inside each egg. The little parasites emerged 

 from the eggs in about two weeks and proved to be one of the two kinds of these 

 minute friends which did gallant work in Ohio vineyards several years ago. It is 

 known to science as Fidiobia flavipcs. As it lives in the eggs of the root-worm 

 there is no danger of checking its goodly work with the cultivation or spraying 

 treatments recommended for controlling this pest. I made no further observations 

 to determine how widely or thoroughly this little parasitic enemy is distributed in 

 the root-worm infested region, but I believe it will be an important factor in re- 

 ducing the numbers of root-worms below the danger limit. But T would not advise 

 any vineyardist to wait for its appearance or to let up a particle in their warfare of 

 cultivation and spraying for the pest. Nature's insecticides are usually very effective 

 in the long run, but oftentimes too slow for man dependent on annual crops. 



