“Worth it” depends on many things, of course.
I live in a project in NYC with a some earth in front, and dogs pee all the time on any bush, plant, etc. It’s just so damn hard to get green sorrel around here, and I’ve heard it grows like weeds. I don’t know, maybe a few plants…
Don’t worry, dog pee can’t hurt you, so it’s okay to eat it! :dubious: I’d rinse it, and get from a plant that looks healthy and not dying from too much pee.
Do you mean Rumex acetosa; wood sorrel is Oxalis sp., sometimes called sourgrass. It’s funny, as a kid, we used to chew on sourgrass and my parents specifically warned me that they could have dog pee on them. They didn’t say this about other edible plants, like Nasturtium or Honeysuckle.
I don’t think it’s the same, but I don’t know what sour grass is. I do know that sorrel is super popular in French dishes, and works off fish wonderfully with a greeny slight tang. The thing is, even here in foodie NYC all I can find, when I do, which is rare, is the reddish kind, which cooks down to purple mush.
Can you hang your own window planter? Any deck railings you could hang a planter box from? Just a thought to avoid whatever may happen to a poor hapless plant on the street.
Maybe there’s a community garden plot in your area? Many people don’t know about them until they’re looking for one. There could also be community gardening groups that plant in common areas like parkways and corners. They get permission from whoever owns the home/building it’s in front of, they put a little fencing around it, and plant flower and vegetable gardens. Could be something to look into for your building, if you can do something “official” you might be able to cordon it off a bit and keep the doggies off of it.
Well, many food crops are fertilized in manure, and we rinse and eat them. I’d say the wood sorrel would be fine to wash and eat (especially cooked). You aren’t likely to get E. coli from it…any more than you would from walking on it with your filthy street shoes. 
Actually, that I would be more worried about.
The last house I lived in before this had a nice-sized yard that had overgrown with weeds. Instead of getting weed killer, I got a book and found out which were edible. We had a lot of lambsquarter done up like collard greens, sorrel soup, purslane salad, etc. in the summer. It was awesome, frankly. My husband would come home and ask if we could have “yard salad” for dinner again! That was all very good fiber, too, I might add…