Less than one-tenth the size of a postage stamp, the sensor consists of an integrated-circuit chip that clips to individual plant leaves and collects and stores information, said Seelig. When the leaves lose enough water to contract to a critical width, the sensor can wirelessly signal computers.
The computers, for example, could instruct individual pivot irrigation systems used widely on Colorado's eastern plains to dispense set amounts of water to particular crops, automatically turning the motors that drive them on-and-off and conserving water and energy in the process!
Source: sciencedaily.comAdded: 5 July 2007