POISON IVY, OAK & SUMAC
'(<a href="http://www.j-archive.com/media/2009-06-29_J_28.jpg" target="_blank">Sarah of the Clue Crew shows pictures of the different plants' leaves on the monitor.</a>)  Poison ivy & poison oak are known for being trifoliate, with three leaflets; poison sumac's <a href="http://www.j-archive.com/media/2009-06-29_J_28a.jpg" target="_blank">leaves</a> are pinnate, from Latin for these avian features'
wings (or feathers)