Just moved to a new place, and these weeds started growing all over. I'm wanting to identify it so I can figure out the best way to get rid of it. They seem to grow only on dry rocky ground, so maybe I just need to patch up the yard with sod? They grow really tall, I've seen one grow 4ft tall in a couple weeks. The stem can get to about half an inch in diameter, and it has a fuzzy texture. The leaves are teardrop-shaped. Here's a photo after I pulled it out (i'm holding it upside-down):
Thanks!