Leaf rollers roll leaves together, then web them in place. Hand pick infested leaves. Four-lined plant bug causes sunken, round, brown spots on the leaves. The injury is sometimes mistaken for a disease. Adult insects are yellowish-green with black stripes.
Scale insects infest the stems and branches.
Close inspection may reveal these insects crusted on the bark. Spray with dormant sprays in the spring. The preferred method of control involves regular inspection to detect the infestation early, then a dormant spray. This information is for educational purposes only. References to commercial products or trade names does not imply endorsement by MSU Extension or bias against those not mentioned.