In an organic garden, instead of using chemicals to kill problem insects, we use a whole toolbox of other ways of thwarting them, and one of the easiest and most effective is to provide a barrier that they just can’t overcome! Barriers are most effective for those insects that don’t fly, but must crawl into the tree to take up residence and do damage, particularly earwigs and garden weevils, but they can also help prevent flying insects like codling moth, which will sometimes flutter up close to the trunk as the female moths emerge from their pupae in the soil in spring.
Read the article in Spring – Week 2.