Q: I have attached a photo of a Japanese maple that we planted two months ago. It has developed a white sticky residue on some of the limbs and trunk. We can see a little white moth looking bug.

A: It’s a colony of planthoppers. Young ones cover themselves with white waxy stuff that sort of looks like white ooze from the tree twigs. In my observation, planthoppers don’t do much damage. You can wash them off with a garden hose.

See Planthoppers