You might wonder why the crop circles are mostly varying shades of green. This is because these are agricultural fields. In the center of each of the circles, there is a pump and a well. You can’t actually see them because of the altitude of the picture.
To each well-head, farmers attach a nine-inch wheel line. This is aluminum irrigation pipes in segments about 20 or 30 feet long, with each of the segments going through the hub of an aluminum wheel that is usually about 6 feet in diameter. On the top of the irrigation pipe segments, there are one or two sprinkler heads. The segments pop together and are clamped, so they form a line directly away from the well-head.
Each of the wheel lines is equipped with a motor that is attached to one of the wheels. The line is moved by using the motor, otherwise, it would be too heavy to move, even though it is made of aluminum.
Since a wheel line is attached to a stationary but flexible well-head, the wheel line moves in a circle. The farmer moves the wheel line a given distance, then he shuts off the motor and goes to the pump and well-head. He starts the pump and opens the valve at the well-head, allowing the sprinklers to deliver water to that section of the field, which has already been planted at that point.
The wheel line is moved a little every day, like the spokes of a wheel, and gradually the crop grows. The result is green circles. The green is of different shades because of different crops and the age of the crops.
If you look carefully, you’ll see that one of the circles has a gray wedge, making it look rather like a leftward facing Pacman. This is because for one reason or another, the farmer that owns that field isn’t growing any crops in that wedge. This is likely due to soil that is rocky or otherwise too difficult to farm.
It sounds like a lot of trouble, but this is one of the only ways that crops can be grown in the desert of southeast Oregon.