Dog Pooping on Concrete and Wood Deck?

My pup is about a year old. I've always taken her out on a leash to teach her the property and to teach her to listen. She recently started to be able to go out without a leash, she is now pooping on the concrete or on the wood trail to our wooden deck and even on our deck a couple times. I stand on the grass and she normally sticks by me. When on a leash she never tried to poop on anything other than the grass. I just don't understand why. Is there anything I can do to help her poop on the grass and only on the grass?