I haven't grown any of these, but that photo of Red Zebra shows a 2-cell and Tatiana's describes it as round. The OP's tomato, on the other hand, looks larger, definitely isn't round, and looks like it's probably a beefsteak type with many more cells. Other stripey bicolors would include Beauty King and Beauty Queen. Beauty King is described as oblate or round. http://t.tatianastomatobase.com:88/wiki/Beauty_King Beauty Queen is slightly smaller but also a beefsteak. http://t.tatianastomatobase.com:88/wiki/Beauty_Queen

Not feverfew or lovage. It looks more like something in the parsnip clan, maybe wild parsnip Pastinaca sativa. FataMorgana Here is a link that might be useful: wild parsnip

I think what I thought was milkweed syriaca (sp) is actually dogbane. I have a growing stand of it way in the back that I've let go for the past two years. It showed up on its own, and if it is dogbane, I'm going to yank it, dig it, destroy it this year. I'm trying to remember what the seed heads looked like, but I'm drawing a blank. I do remember getting the tent caterpillars on them last year, and I've read the dogbanes will get those. So, in answer to your question, that's the only experience I've had with it, and I don't want it to continue. LOL.

Just yesterday I discovered that what I planted out last year as a Stokes Aster is some weed/wildflower that lives in the woods behind my house. Sigh. At least you didn't plant yours out!