By Terry W. Johnson
When we are youngsters learning about the wonder and perils of the great outdoors, our parents taught us a number of valuable lessons aimed at keeping us out of harm's way. For example, we are taught that it is not a good idea to grab a bumblebee, or try to eat every berry we see. We also learned to recognize and avoid poison ivy at all cost. Often parents taught their children this important lesson using a short poem that goes like this, "Leaves of three, let them be."