Hi Susan,

Landscape fabric is supposed to be porous enough to allow water to reach plant roots.  It should not damage the tree.  Over time small particles of soil may impact the porousness of the landscape fabric.  Trees get a great deal of their water from their feeder roots which may extend 15 feet out from the trunk of the tree, further than the fabric.  Here is a link to a question of landscape fabric use:  https://extension.unh.edu/blog/2019/05/should-i-use-landscape-fabric-keep-weeds-out-my-perennial-garden