Two of my vib's, blue muffin and cayuga, get attack by this pest each spring. Later the affected leaves are replaced by healthy new leaves. Any ideas on what this is and how to control them? They do not affect the other vib's I have on the property.
Whatever the pest is it is very small and not immediately noticeable when you unroll the leaf.
Sure looks like standard aphid damage (or a very similar piercing/sucking insect) on newly emerging leaves. The damage shows up best (as you've illustrated) when the leaf is fully formed.
A protectant spray is probably the safest route, rather than a systemic which could harm/kill beneficial insects. Check with your Extension office for what's recommended for these types of insects - which cause this disfiguration similarly on all kinds of plants.