There are many species of scale insects, and there are more than 4 common species that harm seedlings. Mainly include: mulberry white scale, straw sandals scale, pear scale, crape myrtle scale, blow cotton scale, Bai Dun scale, wheel shield scale, ball scale and so on. It is extremely harmful, especially when the plants are dense.

The control methods are as follows:

① Quarantine measures: The scale insects are inactive or have poor activity, and their own transmission ability is limited, but they are easy to spread with the transportation and exchange of seedlings. So quarantine is particularly important.

② Cultivation techniques to prevent proper rotation; Thoroughly clean up the litter in the nursery; Reasonable thinning, ventilation and light transmission; Prune insect branches and burn them centrally; Manual mechanical removal with soft brush; Or wipe it off with a rag dipped in kerosene.

③ When chemical control occurs in large quantities, the turpentine mixture can be sprayed 1 ~ 15 times once in winter to eliminate the overwintering female insects; Before germination in spring, spray 3 ~ 5 Baume lime-sulfur mixture to eliminate overwintering larvae; The newly hatched larvae should be sprayed with pesticides, such as carbaryl and phoxim, on the soil surface around the roots in early spring, and the nymphs on the trees can be sprayed with omethoate, malathion, dichlorvos and fenitrothion.

④ Protect natural enemies and protect some ladybugs, aphid bees and jumping bees.