I would use such a field. Just knowing the state would be great! Clicking on the person who took the pic usually provides an assumption, but it's only ever that. They could have been on vacation. I've asked about having a date too, that the pic was taken. I often wonder when I find a MP pic attached to a plant DB entry, "What month was that?" With a state & date, one can generally see when to expect blooms, gauge spacing, exposure... ("Oh, they grow that in the shade in FL.")
I also love reading others' comments, but to see them, one has to search past the maintenance links under the pic to see if there's a discussion, then click to get to it. Not really attached to the pic. Sorry, I think this is $0.04, I was really trying to keep it at $0.02.