This is the second time I've seen this turkey in my yard recently. I saw it sit down by a dead log and it was throwing up dirt in the air with it's feet and/or wings. It would sit for a minute or two and then stand up and look for a minute and sit back down. It did this for several minutes. After that it got up and walked off. It was a female and my yard has 5 acres with plenty of food and water nearby. Do you think it's making a nest?
They do this to clean themselves of any ticks, mites or other bugs that might get on them. Its called dusting and turkeys do tend to pick a spot that makes them most comfortable in order to do this. It is likely he will keep coming back. If you don't like this, get some coyote urine (or some other predater) and pour it around where he's doing this. It will scare him off for good.