Here is the Red, or Swamp, Maple in a common clumping habit. A sign of forest history can be had from clumping trees--those that grow up in place of a downed (whether by harvest, fire, disease, or pest) solitary tree. This insight courtesy of Reading the Forested Landscape (mentioned in the Catalpa post).
Outside of a dog, a book is man's best friend. Inside of a dog it's too dark to read.