. Injurious insects : how to recognize and control them . Insect pests; Insect pests. GRUBS BORIXG IX STALK OR STEM 137 existence. Early in the season it bores inside the growing tips, causing them to turn down. It is now a slender green worm, marked with bhck dots. Soon it drops from the tips, enters the â sine near the ground, and bores witliin at this point. At tliis stage it is reddish in color, dotted with black, and three fourths to an inch in length. After two or tlu'ee weeks, it bores down and out, and feeds beneath the groimd. just the old roots, sometimes nearly cutting the v
. Injurious insects : how to recognize and control them . Insect pests; Insect pests. GRUBS BORIXG IX STALK OR STEM 137 existence. Early in the season it bores inside the growing tips, causing them to turn down. It is now a slender green worm, marked with bhck dots. Soon it drops from the tips, enters the â sine near the ground, and bores witliin at this point. At tliis stage it is reddish in color, dotted with black, and three fourths to an inch in length. After two or tlu'ee weeks, it bores down and out, and feeds beneath the groimd. just the old roots, sometimes nearly cutting the vine oflf. It now reaches a length of two inches, is thick bodied, wliitish, and marked â with fuie brown dots. A pupal stage is passed in the soil, the fall and some in the spring. Tips sho'n^ing the work of the earlier stage should be pinched off and destroyed. The grubs working in the soil may be dri\en deeiser to the old roots by puUing away the dirt for a few days, later heaping ashes aroimd the vines. On the old roots thev will do httle Fig. 1-'5. â .\dult of the Hop-plant Borer. Original. Some of the adults emerge in The Cabbage Curculio (Ciutorhi/ncus rajxr Gyll.) A small snout beetle appears on cablxige plants early in the season, us- ually while the plants are still in the seed bed. The Ijeetle is one eighth of an inch long and varies in color from gray to black. Its body is quite broad. Eggs are laid in the stalks, and a whitish grtib tunnels witliin. Infested plants may ch'oop o^"er in their upper half, or break off m transplanting. The grub is full grown in tlu'ee weeks, trans- forms in the soil, and the adults emerge a week later, disappearing after a few days. There is one generation amiualh-. Various wild plants, espeeiaUy hedge mustard and wild jiepper- grass. are nati^ve food plants and are preferred to cabliage. Use may be made of these as traps, destroying them as soon as the lieetles have laid their eggs in them. An appUcation of arsenate of
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