In this tree identification episode, Purdue Extension forester Lenny Farlee will talk about how American elm leaves have jagged edges with a large tooth and then smaller teeth like edges on top of it.

It’s a sunny September day in Castine, Maine, and I’m standing in a stranger’s yard debating how best to hug a tree. Not just any tree, but an American elm, a fully mature Ulmus americana. I want to ...