1. Starscream

The red spider of Rhododendron mainly occurs on the back of leaves. When the occurrence is large, the back and tender shoots of leaves are also distributed. After the occurrence of red spider, its leaves will appear small yellow and green scattered spots

Control method: create a well ventilated environment, make the Rhododendron grow healthily and increase the resistance to red spider. If the occurrence amount is relatively large, the important area can be cut off to reduce its mouth volume; If there are many and dense branches, they can be sprayed with nicotine biological insecticides such as avermectin

2. Cuckoo net bug

Rhododendron webbug mainly occurs on the back of the leaf. When it occurs, some black spots and small insects with transparent wings about 2-3mm long will be seen on the back of the leaf. Yellow and green spots will also appear on the front of the leaf, but they are smaller than those in the case of red spider. When it occurs, it diffuses from leaf vein to leaf edge, and the occurrence degree of leaf center is significantly more than that of leaf edge

Control method: if there are few pests, the diseased leaves can be removed and burned to prevent re infection. If there is a large amount, imidacloprid can be used to prevent it

3. Aphid

Aphids mainly occur on the back and tender tips of leaves. There will be some small green and white insects, some with wings and some without wings, which are usually clustered together

Prevention and treatment method: when a small amount occurs, it can be washed away under the faucet; Or hang some yellow armyworm boards around the azalea; It can also be prevented by soaking tobacco water. If the amount is large, imidacloprid can be used for spraying. After 3-7 days after using the first medicine, the second medicine should be used to kill the larvae without hatching in the eggs