Visit the link too, the pic is hilarious. http://www.duluthsuperior.com/mld/duluthsuperior/15387040.htm
Yes, I'm sure that it was all the work of some pranksters. If I was going to prank someone by planting weed in front of thier house, I'd actually put it in front of a door that people use.
If she didn't know that it was marijuana why did she bother picking a leaf to show someone for evidence? She just doesn't want people thinking she's a toker.