our vet told me, even if the pee thru the day, dogs only poop once a day unless they are sick. I think once they "go" somewhere its marked and they go to the smell. Maybe rinse down the area, or if you have soil there put some fresh on top and place a bowl of vinegar on the spot for awhile. Then, when he has to go walk him where you want him to go and take some time, dont rush him. Once he goes he will tend to go to that area. He may just want your attention.
I have 7 dogs "on the farm", they go everywhere. I have 1 dog in town w/ me. He has an enclosed area where he started to go. He pees on trees in the back, but when he has to poop he'll dance around the gate, if its closed, til I let him into where he goes. Its nice of him, lol, I can clean the area up every few days fast, and its not where I walk . (also, the more "real" food they eat - more real meat, not the dry pkged stuff, it breaks down faster in the yrd.) sharet