Town of Windsor: Esposti Park

On the way to somewhere else I got lost in my own backyard and happened to see this small park on the Redwood Highway.

Too bad I didn't have a dog along because other canines were present. So I walked myself around the baseball field and noticed the fence and Do Not Enter sign in front of this tree.

Now I am puzzled. There are more oak trees in our area than stars in the sky -- so why is it necessary to cordon off this "Heritage Tree #4" in Esposti Park?  If I learn the reason I'll add onto this post.