Are billions needed for saving western Kansas?

Flying east to west over Kansas, the land transforms from lush green to desert brown. Rectangular farm plots fill in with emerald circles, the work of center-pivot irrigation.

Outside Garden City, in the middle of one of those circles, Duane Roth scoops up soil to reveal an inconspicuous PVC pipe. It’s a soil moisture probe that tells Roth exactly how much water his crops need. The device is one of many new technologies designed to help farmers make the most of every drop.

“All that you have to do is open up your app,” said Roth. “It’s going to tell you, you don’t need to irrigate or you’re going to need to apply an inch within six days.”