Introduction to Control Methods for Scale Insects on Pear Trees

The control of scale insects on pear trees should adopt comprehensive measures of strengthening agricultural control, timely application of efficient and targeted pesticides, and protection and utilization of natural enemies:

First, reasonable fertilizer and water management should be carried out to enhance tree vigor and reduce damage. In winter and spring, combined with pruning, dense branches and branches with severe pests and diseases should be cut off to make the canopy well-ventilated and allow light through.

Second, pesticide spraying should be carried out at the right time. Seizing 3 suitable control periods throughout the year can basically control its occurrence and damage. The first is from late April to early May, during the peak occurrence of the first generation of young scale nymphs, when pesticides should be applied in time to reduce the insect source; the second is from September to October, after the autumn shoots of lychee emerge neatly, to protect the autumn shoots and help them become robust and mature; the third is winter orchard cleaning. The highly effective targeted pesticide is 40% Supracide emulsifiable concentrate, which has a strong penetrating effect and is highly effective against scale insects. Since the 1980s, our city has consistently used this pesticide as the first choice for controlling lychee scale insects. When applied during the peak period of young nymphs, it can be diluted with water 1000--1200 times; if the suitable control period is missed, then use 700--800 times, which has a good control effect on older nymphs and female adult scales; for winter orchard cleaning, it can be mixed with 95% mineral oil emulsion for a better effect, generally using 40% Supracide emulsifiable concentrate at 1500 times plus 95% mineral oil emulsion at 300 times.

Third, do a good job of protecting and utilizing natural enemies. Lychee scale insects have many natural enemies, such as ladybugs, chalcid wasps, and predatory thrips. By protecting them through rational pesticide use or releasing artificially reared natural enemies, a certain population of natural enemies can be maintained in the orchard, which can provide good control of lychee scale insects.