The leaves on a red-twig dogwood started showing holes until some were like lace and a few died. There are what look like skeletons of tiny white flies on some of the leaves. There are also white deposits, usually next to the holes in the leaves. There are very small worms (larvae?) on the undersides of some leaves. These are in groups, and they start out in spirals, with all the spirals laying flat in a group, touching each other. The worms are a pale gray with a moist mildew-ey almost furry look. The backs of a few leaves have lots of small brown spots, but this might be a separate problem -- or they might be eggs?
What is this, and will it harm the bush in the long run if I don't treat it?