Sensor Network – Sap Flow Sensors

With changes in climate, it is important for scientists to understand how plants respond to changing moisture levels. Dr. Chris Still has installed sap flow sensors on three different tree species to monitor water flows, one response to changes in moisture.

Increasing evidence over the last 20 years shows that water movement in trees is complex. Water does not just move from soil to roots, stems, leaves, and then the atmosphere. Water can move upwards, downwards and from side-to-side depending on greatest demand, leaving the impression that plants exhibit “behavior&”. Using the Heat Ratio Method (HRM) developed in Australia, RMBL researchers can measure sap velocities and sap flows in stems, branches and structural roots of woody plants. Low and zero sap flow rates, as well as reverse sap flow rates, can be measured virtually continuously with a high degree of accuracy using HRM, allowing water flows to be monitored in a wide variety of species, sizes and environmental conditions including drought, in the RMBL Research Meadow.

Sap flow data are currently unavailable online.