Absolutely. If by "related" you mean like how you are related to your mother or any other person, then yes, you are related to trees. But you - and every other human - is related to every other living thing as well. We all have shared ancestors. My sister and I have a shared ancestor that goes back one generation, to our parents. If I go back two generations, anyone that I share a grandparent with is my first cousin. If a person and I share a great-grandparent as an ancestor, then they are my second cousin, and so on. Go back far enough, and we share an ancestor with every other living thing, including trees. We are all cousins.