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How to control pests on the underside of azalea leaves?

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(1) Red spider mite. The individual is extremely small, with a body length generally around 0.3 mm, difficult to see with the naked eye, and observation requires the aid of a magnifying glass. The body is red, and it often gathers on the underside of leaves, mainly sucking the plant's sap and causing grayish-white spots on the leaves. In severe cases, it causes the leaves to turn yellow and drop, new shoots grow poorly, and the tree vigor weakens. Red spider mites produce 10 generations a year, and the damage is especially severe during high temperature and drought from June to August, but the damage is lighter during heavy rain and rainy weather. In winter, dead branches and fallen leaves should be cleared away to eliminate overwintering adults

(1) Red spider mite. The individual is extremely small, with a body length generally around 0.3 mm, difficult to see with the naked eye, and observation requires the aid of a magnifying glass. The body is red, and it often gathers on the underside of leaves, mainly sucking the plant's sap and causing grayish-white spots on the leaves. In severe cases, it causes the leaves to turn yellow and drop, new shoots grow poorly, and the tree vigor weakens. Red spider mites produce 10 generations a year, and the damage is especially severe during high temperature and drought from June to August, but the damage is lighter during heavy rain and rainy weather. In winter, dead branches and fallen leaves should be cleared away to eliminate overwintering adults. When damage begins in March, spray to kill with 10% fenbutatin oxide emulsifiable concentrate at 1000 times dilution, 7051 insecticide (miechongling) at 3000 times dilution, or pyridazinone (spiromesifen) at 1000 times dilution.

(2) Pear lace bug, also called armyworm bug. The adult pear lace bug is grayish-white, winged, and flat in body shape. It often gathers in groups on the underside of leaves to suck sap, causing the leaf color to turn yellow-brown or even white, and the underside of the leaves has yellow-brown rust-like spots formed by secretions. After being damaged, it causes early leaf drop, affecting growth and ornamental value. The pear lace bug's damage period is from May to October, with more occurrences in summer and autumn, and the damage is even more severe especially when the weather is dry in August. Fallen leaves should be cleared away to reduce the number of overwintering insects. When the first-generation larvae occur in early to mid-May, pesticides such as 40% omethoate emulsifiable concentrate at 1500 times dilution or insecticide at 2000 times dilution can be sprayed.

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