My parents have a willow in their backyard which they planted around six or seven years ago. Since the backyard gets really really wet the tree has grown extremely fast. That was the main reason they planted it, to take control of the drenched floor. But now I notice some really ugly growths all over and around the trunk. Black to dark red growths and many areas with white puss and in the puss are some kind of insect, that looks a little like a small woodbug, but it's not a wood bug. The growths seem to produce their own shallow holes, they don't stick out so to speak. Small areas of outlier bark crumble off easily. When you go up close to the tree it looks really bad. Is this tree done for? Try chemicals? Cut it down?
Sounds like a fungus. What to do depends on what it is and what condition the tree is in at this point. Maybe something happened to kill part of the stem and the fungus is decomposing the already dead trunk portions.
Thanks, My mom spoke to someone at a nursery today, and they said it was probably the tree's sap. But I dunno. I will try and get some photos up.