The IRROMETER was first developed in 1951 to help growers improve irrigation efficiency. It provides the user with accurate information on soil moisture status regardless of soil type. The instrument measures in centibars (cb) or kilopascals (kPa) of soil water tension. This value represents the energy a plant’s root system uses to draw water from the soil. Understanding soil moisture activity helps the user make informed irrigation scheduling decisions resulting in improved yield and quality while reducing water, fertilizer, labor and energy costs.
In use since 1978, the patented WATERMARK sensor is a solid state electrical resistance sensing device that is used to measure soil water tension. As the tension changes with water content the resistance changes as well. That resistance can be measured using the WATERMARK Sensor.
The sensor consists of a pair of highly corrosion resistant electrodes that are embedded within a granular matrix. A current is applied to the WATERMARK to obtain a resistance value. The WATERMARK Meter or WATERMARK Monitor correlates the resistance to Centibars (kilopascals) of soil water tension.
The WATERMARK is designed to be a permanent sensor, placed in the soil to be monitored and “read” as often as necessary with a portable or stationary device. Internally installed gypsum provides some buffering for the effect of salinity levels normally found in irrigated agricultural crops and landscapes.
IRROmesh is a compact, solar-powered, wireless system for in-field measurement of soil moisture, temperature, and other parameters. Sensor data from each node is routed through an interactive mesh network back to a central point where it can be uploaded to the web and made accessible to anyone with an Internet enabled PC or smart device, or stored locally for collection. Each node is capable of reading three soil moisture sensors and a soil temperature sensor, along with inputs for recording irrigation events and rain gauge data.
The WATERMARK Meter is a hand held device designed for reading WATERMARK sensors in the field. The digital readout displays the sensors’ soil moisture status in centibars (cb) or kilopascals (kPa) of soil water tension. This value represents the energy a plant’s root system uses to draw water from the soil. Whereas higher tension values indicate dryer soil, lower tension values indicate wetter soil. The meter’s replaceable cable assembly has spring loaded clips for attaching to sensor leads. Users only need one meter to read any number of WATERMARK sensors. The meter comes in its own nylon case, padded and zippered for safe keeping when not in use.
