The Leaf Wetness sensor measures leaf wetness with a grid-like, resistance based sensor. This sensor can be connected to a WatchDog A-Series Data Logger. It mimics moisture on vegetation from 0 (dry) to 15 (wet). It is a circuit board with interlacing gold plated fingers. Condensation on the sensor lowers the resistance between the fingers, which is measured by the WatchDog A-Series Data Logger.