I think the most effective and fun way to identify trees is to begin by learning some general distinguishing features of groups and families of trees.  You can, of course, identify a tree with a good taxonomic key, but then you will have only learned a single tree (I will, of course, discuss using keys later and recommend quality field guides that include comprehensive taxonomic keys).

Here are some areas that will be addressed in my Trees of Pennsylvania series on tree identification:

• We begin by discussing the different basic leaf types
• Then we will look at basic features of twigs and leaf arrangements that will help to narrow the options
• This will be followed by a series of posts on identifying some of the more common Pennsylvania tree species.

While providing these posts over the next several months, I will also be developing the Tree Profiles feature. Eventually, I will also add a Trees of PA Identification Key.