INSECTS INJURIOUS TO SMALL FRUITS 



GRAPE PESTS 



Over 100 insects recorded in this country on the 

 vine. 



The grape phylloxera ^ {Phylloxera vastatrix) 

 Order — Hemiptera 



This insect has always existed in this country 

 on wild vines but not very injurious here; very 

 destructive in France; it exists in two forms, one 

 on the leaves and one on the roots ; the root form is 

 much the more injurious one. 



The true sexual eggs are laid in the fall on old 

 wood and hatch the following spring; the young 

 lice go to the leaves and form galls on -the lower 

 sides; in these galls a female may lay 500 or 600 

 eggs; there may be 6 or 7 generations a season on 

 the leaves ; young of later generations pass to roots 

 and winter there ; the root-forms cause galls on the 

 roots and great injury; winged females issue from 

 cracks in the soil in fall and go to the stems of vines 

 where they lay 2 to 8 eggs; these eggs are of two 

 sizes, the smaller yielding males and the larger 

 females; the true females are small with rudimen- 

 tary mouthparts and each lays a single true tgg. 



1 Marlatt— U. S. Dept. Agr., Ear's' Bull. 70. 

 Quayle— Calif. Expt. Stat., Bull. 192. 



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