Took some more pictures today of the bees working the nectarine tree. I notice that Honey bees have a much easier time flying around and visit far more flowers than the mason bees. But whenever the mason bees do enter a flower they come out completely covered in pollen. I think it's their weaker wing that prevent them from flying the great distances that honey bees do. I believe the smaller size of the mason bees allows them to reach more parts of the flowers too but we'll see who the better pollinator is. If nectarines didn't produce only one seed (I think) I might have marked what flowers are visited by what bees with ribbons or paint or something.
This is all that's left of the caterpillars and I'm wondering why I ever though they'd be a threat. I removed two clusters of them out of fear they might devour the tree. There were still quite a few groups of them left and lots that had spread around on their own. I don't know what happened to these other groups but there's only a few of them left. Because they're only on the one branch I don't think they're going to harm the end harvest if any.