fuzzy white growth on tree

Question

I have a willow tree that has something growing on it. It’s got fuzzy white on it and it going down my tree.

Answer 1

It would be helpful if I can see a picture (you can send one attached to your answer notice email). But, off the top of my head, I would suspect that you have woolly aphids. This article may help:
https://www.gardeningknowhow.com/plant-problems/pests/insects/woolly-aphid-control.htm