I've seen this once or twice in my neighborhood, and it now appears to be thriving in my wildflower garden. It appears to be invasive, as I have also noticed it spreading in the less dense parts of my neighbors lawn. It appears to have been stunted by the dry summer this year, the ones I had seen before were about 18-24 inches tall.
I have some thoughts on what it might be, but before I embarrass myself with a wrong answer, would you be able to post where in the world is your neighbourhood? Province or state would be fine, if it is in North America...
I've been wracking my brain over this one. It looks familiar, but I kept on coming up empty-handed when looking at the plants I thought it resembled. However, I spoke with Douglas Justice this morning about it, and he recommended either a Geranium or Erodium (or near relative). I agree - but it doesn't seem to match any of the listed Geraniaceae species found natively (or introduced and known) in Minnesota. Perhaps it is a garden escape? Would you be able to get a closer picture of the flower or fruit?
Leaves of images that I've seen of this are fairly variable, so it's a possibility. A good picture of the flower will help.
Thanks to all! I have attached a closer picure of the flower. I do believe that it most likely is Tanacetum Parthenium based on pictures of I have found at other sites. It may have helped had I noted that the leaves are very aromatic (or maybe not - I only found one site mentioning this attribute of Tanacetum Parthenium).