I hunt elk from the get go of the season, and according to the Sept. 4th opener, I might guess your hunting MT? If so, it's usually very warm still. This in return makes bulls want and need to stay cool. Of course they are going to need water and if you can narrow down where the water is, then that's always a good idea to sit by. Wallows are great as well. If you find a bull that is in fresh mud, I would try to find the wallow he used, they tend to return and use the same one in order to stay cool and keep spreading their scent. It's something to try. Good luck
HuntinGuy