what kind of spider web is this and will it hurt my trees
The spider is located at the center of the web. It is most likely a Cribellate Orbweaver in the Uloborus genus. They make these webs to hide their egg sack’s as well as themselves from predators.
Furthermore, I am not aware of any spider being naturally harmful to trees. Especially if it is just one of these smaller Orbweavers.