Under leaves look white from waxy threads produced by the scale. Dark mealy or spongy to somewhat crusty fungus growth on leaves and sometimes stems. First, control the insect causing the problem, then apply Oil to loosen mold. Use appropriate miticide. Small bug has two distinct bands.
Blotches appear on underside of leaf causing distortion, stunting, discoloration, or even necrosis.
May find spittle masses on the lower stems. Small insect about 0.5 mm long. Vary in color but usually white or light. Heavy population around holly and citrus bloom. New growth will be off color and deficient looking.