Japanese beetles can be a major pest for certain tree species. The adults emerge generally in the first week of July and feed on a variety of tree species. Some of their favorites include lindens, crab apples, plums, and crimson maples. They can also generally be found on cherry trees and certain varieties of willows. The feeding adults are easily identified by their iridescent coloring and the lace-like pattern in which they leave the leaves.
Control is targeted toward feeding adults with two properly-timed sprays. Using the correct chemical it is possible to kill all present adults. There is also some residual that remains on the leaf that any later feeding adults can ingest which will kill them off, as well.
One of the best things to do is to avoid placing specific Japanese beetle traps on your property, as generally, all this does is attract them to your property, which can increase the likelihood of damage on your trees and shrubs.