Sounds like caterpiller egg infestation. Sevin for now but read the lable for amount and water content..............keep children & pets away from this until it is dry if you do this when the sun passes it will dry during the night...spray only when no wind ...........wear old long clothes, hat, mask, goggles and gloves..................in the fall use dormant oil according to directions and also dormant oil in the spring read the label carefully and the same rules apply for equipment.