苹果开花前后指从苹果发芽开始至落花后10￣15天,时间上大体在3月下旬至4月下旬。此期大部分越冬害虫已开始活动危害,天敌益虫也相继出蛰活动。这个时期的综合防治工作,一方面要抓紧对主要危害对象的防治,另一方面要注意保护天敌,尽量使用对天敌影响不大的选择性农药,或在施药 Apples before and after flowering from the apple sprout began to fall 10 to 15 days after the time roughly in late March to late April. Most of the overwintering pests in this period have begun to endanger the activity, and natural enemies benefit insects have also been out of sting activities. In this period of comprehensive prevention and control work, we must pay close attention to the prevention and control of major hazards, on the other hand, we should pay attention to protecting natural enemies, try to use selective pesticides that have little effect on natural enemies,