Hi popmoma that appears to be Ambrosia artemisiifolia - Ragweed. Achooo!

Yes that looks correct, pren.all! I'm pulling it. The foliage was so pretty that I thought it was going to turn into something good. I've never seen any other one like it in my yard, so maybe the seed came along for a ride with all the zinnia seeds.

I didn't experience any sneezing from it, but I'm fortunate in that I seem not to be allergic to anything. But I definitely do not want that to seed itself anywhere else, so I just yanked it out. Thank you for your help!

You are most welcome! It really is an attractive plant as weeds go. Yes it could have come with your Zinnias or just blown in. The pollen is dispersing now and peaks in Sept. But it can start in June and go until Nov.

I have only seen one seedling this year and yanked it right away. I had pulled a few in previous years and keep on it for every ones sake. My DD's BF is allergic to all pollen. Happy you were not affected by it. I don't have any issues either thank goodness because I am rural and it can get a really good foothold in the miles of unkept areas.