The shape of trees, in part, is caused by genetics. A Red Maple has a different shape and structure than an American Elm tree ...

American elms are elegant and beautiful native North American trees. Sadly, their numbers have been decimated by Dutch elm disease, which is caused by a pathogenic fungus called Ophiostoma novo-ulmi.

Barking up the right tree: 80 photos were sent in by 15 readers displaying their skills with images of trees. Here are the ...

Above: Siberian elm samara in New York City. Like other fruit, nut, and winged seed trees (like maples), elms can have mast years, or a bumper crop, where branches appear to be bursting with ...