I think it's tansy, Tanacetum vulgare, and sure, let it grow if you like it. You'll probably find them seeded all over your yard, but if you don't mind - and I wouldn't - enjoy it.

I don't know this one nor do I have it, but I do let certain native annuals grow around our place. They can be lovely when we get enough rain. My favorite is desert primrose, wow, what a wonderful fragrance and a beautiful blossom

@judy - great! anything with "vulgare" as part of its botanical name is welcome in my yard!! :-) I did find a couple more - which I'm glad to see since I've been fighting a ten year battle with prostrate spurge and some icky, prickly things, the more native wildflowers and annuals I can get growing, the better!

@softmentor - I agree, I'll let most of them grow. I'm trying to get some Mexican primrose to take (I know - they take over - but I've got an acre of emptiness to fill) but the bunnies are determined to shear it to the ground!

zzini,

That looks cool, do you have a close-up shot of the blooms?

MM

@mangledmind - here's a close-up, it's a little fuzzy, but you can see they're just little puffs of yellow. My friend thinks it's an invasive-ish weed so I'll have to keep an eye on it!
{{gwi:402862}}From Plants around the homestead

One person's invasive weed is another's wildflower.:-)