Australian inventor Ken Uzzell's probe accurately measures soil moisture without being affected by chemicals, fertilizers, sewage, or earth movements caused by tractors or ground tremors. The patented plastic tube and crushed rock probe measures to within an accuracy of +/-1 percent, according to Uzzell. When in operation, the probes are linked to a computer monitoring system that analyzes data on water contentin order to signal when irrigation is required. Dtat from the probes are combined with information from weather satellites to generate an advanced watering schedule. Nutrients and fertilizers may be added to the system, and air can be pumped through the system during floods to reduce waterlogging.