Insect and Fungous Enemies of the Grape. 9 
LIFE HISTORY. 
The adult beetles appear to feed exclusively upon grape, wild and 
cultivated. They appear in vineyards in the spring about the time 
the Concord grape is in blossom, and spend 10 days or two weeks 
feeding on the foliage before beginning egg laying. The feeding 
marks are characteristic and occur on the upper surface of the leaves 
as short, somewhat curved lines, usually in groups, as shown in fig- 
ure 7. The presence of this insect in 
vineyards can be detected best by these 
- feeding marks on the leaves. 
Eggs are placed singly in little cavi- 
ties cut into the fruit (fig. 8), and the 
resulting larvee bore into the flesh, feed- 
ing also on the seeds (fig. 9). After 
about three weeks the grubs have at- 
tained full growth and go to the ground, 
where they construct little earthen co- 
coons from which the parent beetles 
emerge in the course of three or four 
weeks. After emergence the new brood 
of beetles feed on grape foliage until 
the approach of cold weather, when 
they seek shelter under trash of various 
kinds and hibernate until the following 
spring. 
CONTROL. 
Because this insect feeds on the upper 
surface of grape leaves for some time 
before egg laying, it can be successfully 
controlled by arsenical sprays, such as 
arsenate of lead. Several times prac- 
tically complete freedom from this pest sic, s—Grape curculio in act of 
has been obtained by the use of this ¢xcavating egg cavity on grape 
poison at the rate of 14 pounds of the eee watt a 
powder or 3 pounds of the paste to each 50 gallons of water or Bor- 
deaux mixture. The first application is given just after the blossoms 
fall and the second three or four weeks later. Vineyards sprayed 
according to the grape-spraying schedule (p. 74) will be practically 
free from attack by the grape curculio. 
THE GRAPE BLOSSOM MIDGE:.' - 
The grape blossom midge is a rather recent addition to the list 
of American grape pests, having been first recognized in 1904 in the 
®Contarinia johnsoni Slingerland. 
48533 °—21—Bull. 1220 
2 
