. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. THE HOP FLEA-BEETLE. 77 brown freckles as the leaf grows and expands, the skin at this point in time becoming torn and frequenth^ showing holes. When the beetle occurs in moderate numbers the leaves (fig. 14) become riddled, as by fine shot, the i^unctures being most obvious after the plants have made some growth. In its attack on hops it frequently causes the leaves to look like a mass of network or more or less completely strips the vines of leaves, as shown in figures 15 ajid IG. As is the case with fiea-beetl
. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. THE HOP FLEA-BEETLE. 77 brown freckles as the leaf grows and expands, the skin at this point in time becoming torn and frequenth^ showing holes. When the beetle occurs in moderate numbers the leaves (fig. 14) become riddled, as by fine shot, the i^unctures being most obvious after the plants have made some growth. In its attack on hops it frequently causes the leaves to look like a mass of network or more or less completely strips the vines of leaves, as shown in figures 15 ajid IG. As is the case with fiea-beetles in general, this species does most harm to 5''oung plants. When the beetles occur in considerable numbers they are capable of doing great damage in a comparative]}' short time, com- pletely devouring the young and tender leaves as fast as they come up. Injury is most n o t i c e a bl e on hops, sugar beet, rhubarb, and some other vegetables. The beetle is a general feeder, the list of its food plants including, among vegetables, rhubarb, beet, cu- c umber, turnip, radish, cabbage, mustard, and po- tato. It feeds also on hops, red and white clover, nettle, dock (liumex), lamb's-quarters (Chenopodium), pigweed and tumbleweed {Amaranthus retrofexits and ^1. gpacians). hedge mustard, and common wild-growing black mustard. The prob- abilities are that, as all of these plants are affected by the adult beetles, a considerable proportion of them serves as food for the larva*. On this head Mr. Quayle has written that the eggs, larvjc, and pupa» were taken at a depth of from three to six inches from the surface of the ground in hop fields and that the larva? apparently feed on the roots of hop as well as those of other plants growing in the yards. Since it is well known that the beetles occur in other regions where hops do not grow there must be other larval food plants. It would be interesting, and is important, to ascertain exactly what plant, or plants, is the favorite with the la
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