Control methods for red-bellied white tiger moth infestation in October flowers

In October the weather gradually turns cooler, but you still need to pay attention to timely control of flower pests.

Red-bellied white tiger moth: also known as the human-marked white tiger moth, it is a leaf-eating pest with a very broad diet. It mainly harms woody flowers such as wintersweet (Chimonanthus praecox), rose of Sharon (Hibiscus syriacus), ornamental peach (Prunus persica), Chinese rose (Rosa chinensis), elm (Ulmus) and rose (Rosa), and also harms herbaceous flowers such as African daisy (Gerbera jamesonii), dianthus (Dianthus), chrysanthemum (Chrysanthemum), lotus (Nelumbo), peony (Paeonia lactiflora), daylily (Hemerocallis) and iris (Iris). In severe cases it can eat all the leaves of an entire wintersweet or Chinese rose plant. Its adult features are a red back and a yellow-white underside on the abdomen; the wings are white to yellowish white, with one small black dot above the middle cell of the forewing and an oblique row of small black dots outside the middle cell and along the posterior margin. At rest the two wings are folded over the back, and the small black dots on the left and right wings merge into the character for "person." The male's hindwings are orange-red, and the female's hindwings are white.

The larva's body is yellowish brown, with a black head, a yellowish brown dorsal line, and a pair of hairy warts on the back of the mesothorax and the first abdominal segment; each abdominal segment has 10—16 protrusions, and several protrusions bear clusters of pale red long hairs; above the spiracular line is a broad dark yellow band. In the Yangtze River basin it produces 3—4 generations a year, overwintering as a pupa in the soil and beginning to emerge in April of the following year; adults often rest quietly in hidden spots among branches and leaves during the day and are active at night, with obvious phototaxis. Females mostly lay eggs on the underside of leaves, in masses or arranged in rows, with an egg period of about one week.

The larvae have a death-feigning habit, and newly hatched larvae have the habit of feeding in groups, mostly eating the leaf mesophyll; after the third instar the larvae disperse to feed, and can eat the leaves completely clean, leaving only a few bare branches. April to October is the larval damage period, and after October the mature larvae pupate to overwinter.

Control measures: clear away weeds and fallen leaves and twigs around flower and tree plants such as wintersweet and Chinese rose, and burn them in a centralized way; deeply plow the soil to destroy overwintering pupae; remove egg masses and leaves with clustered newly hatched larvae and destroy them; at the newly hatched larval stage, use 20% fenvalerate at 2000 times dilution, or 90% trichlorfon crystals at 1000 times dilution to kill the larvae; from May to August, when the leaf mesophyll on plants is found to have been eaten into a net-like or notched pattern, spray pesticide as early as possible for control; during the spring adult emergence period, hang black light lamps to trap and kill them, which can greatly reduce the damage the larvae may cause that year.