I am a retired school administrator and was driving tractor on a farm east a couple miles east of Prescott, WA. Near the top of a steep sidehill, I could look down on the field below me and saw three large circles in the soil. The circles appeared to be 70 to 100 feet in diameter. Having grown up on a farm, I know of no explanation for them to appear in the soil. They looked like perfect dark circles. I asked the owner of the farm if he knew of anything that was done at that location that could have caused them and he said no. On the sidehill in which they were located, I don't know how any man-made circles could have been made. I can think of no explanation for them.I didn't have a camera with me but they are located above a gravel road so would be easy to access on foot by climbing the hill.