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I agree with gardenguykin, looks like Eupatorium capillifolium to me as well. The pictures in the first link don't look like any pics of the plant that I've seen other places, but maybe it's because it's a closeup of a young plant (young plants can sometimes look a bit different than the adults). Your second link doesn't take me to any pics of the plant so I can't comment on that. Check out the pics posted here, I think you'll see many of them resemble your plant: http://davesgarden.com/guides/pf/go/54505/
I did go back to the plant and examined the lower leaves and compared those to the online pics and they are a match. Somehow the upper leaves just look very different, maybe due to a high nitrogen boost from fish fertilizer...
But thanks to both of you for your help. I removed the plant from the veggie patch right away.