Residual Pore 
A micropore size of less than 0.0002mm in which the water is held very tightly that it is unavailable for plant use and is a stage at which permanent wilting point would occur in a plant.
Residual Pore
A micropore size of less than 0.0002mm in which the water is held very tightly that it is unavailable for plant use and is a stage at which permanent wilting point would occur in a plant.