I have several tomato plants which are generally doing well. They are 5'
tall in the northeast US. However, some of them have tiny, wrinkled leaves
on the upper 2/3s of the plants, but the lower 1/3 are normal and healthy.
They almost look as if someone picked all the leaves off the upper stems
leaving a little bit of leaf behind.

What would cause this and what does it mean? All but one of these plants
are Sweet 100 cherry tomatoes.