Herbs that Drain Dampness

Besides promoting urination to drain dampness, what is another important function of Fu Ling (poria)?

Fu Ling both drains dampness and strengthens the Spleen. It is very commonly used in formulas that tonify Spleen qi.

Source: Bensky, D. (2004). Chinese Herbal Medicine: Materia Medica. Seattle, WA: Eastland Press. p. 267 [Q819]