Sometimes you need to think ''outside the box'', Hundreds and thousands of years ago there may have been more moisture and vegetation than is now present in your vicinity. In more arid areas you may want to check out near and adjacent to old river beds. Also ask around (older folks) about any old springs, and look for places that would be protection from the elements. If there are any mountains or hills in the area, always check the saddles between canyons and along the slope that goes down from these saddles.