An analysis of Granier sap flow method, its sensitivity to heat storage and a new approach to improve its time dynamics

Granier sap flow method is a simple and easily applicable method to monitor sap flow in trees in field conditions, and is thus in wide use. However, it has been suggested that the method is slow to capture transient changes in actual sap flux density due to heat storage and release within the stem. We show here how this may lead to biases in the estimation of the dynamics of sap flux density especially at low flow rates when thermal diffusivity...