BULLETIN 192. 



INSECTS INJURIOUS TO THE VINE. 



117 



This insect has done considerable damage in this State within the 

 past two or three years, and promises to be a serious enemy of the vine- 

 yardists unless held in check. The grape-root worm of the Eastern 

 States, identical in all important respects with this one, is one of the 

 most serious pests the grape-grower in that region has to fight. 



The insect injures both the roots and the growing parts of the vine 

 above ground. It is a small beetle, about one-fifth of an inch long, and 

 either black or brown in color. There is no mistaking its identity from 



FIG. 6. Leaf eaten by root beetle. 



the way it eats out chain-like strips from the leaf, or gouges out similar 

 strips on the shoots and other growing parts. 



Life History. The adult beetle appears in May, having emerged from 

 the ground where it has been since the previous year, and where it has 

 passed through the larval and pupal stages. It begins at once to feed 

 upon the leaves, eating out narrow slits about one-twentieth of an 

 inch wide and from one-fourth to three-fourths of an inch long. It 

 attacks the shoots, petioles, pedicels, and to a less extent the berry 

 itself in the same way. 



After feeding for a couple of weeks, egg-laying begins. The eggs are 

 deposited on the inner bark, or in crevices, usually beneath two or 

 three layers of the old bark. They are laid in clusters of from four or 



