DEN5: for differential measurement of xylem, phloem and total tree diameter.
The DEN5 is capable of measuring Xylem and phloem tissue diameter and thickness fluctuations and is ideal for extracting information about vessel refilling and embolism repair of the xylem, and the phloem transport of water and sugar.
With measurements in millimetres, and a resolution of 0.001 mm, the range is between 0-6mm.
The DEN5 use a pair of Differential Variable Reluctance Transducers (DVRT) to measure the fluctuations in the xylem and phloem tissue. These DVRTs, mounted in a stabilised frame, are secured to the heartwood of the tree using a thermally independent invar-36 rod. This removes the effects of thermal change on the measurement, providing an accurate measurement of the phloem and xylem.
With a DVRT mounted against the bark (insulated with a thin film of silicone vacuum grease) and one against exposed xylem (again insulated with silicone vacuum grease), the changes in the xylem and phloem can be calculated. This data is stored on the logger’s internal MicroSD card for downloading as a CSV file.