Herbs that Clear Heat

Besides clearing heat, what is another important function of Sheng Di Huang (rehmanniae radix)?

Sheng Di Huang is sweet in flavor meaning it can tonify and moisten. It is used for yin deficiency with heat signs, as well as injury to fluids.

Source: Bensky, D. (2004). Chinese Herbal Medicine: Materia Medica. Seattle, WA: Eastland Press. pp. 120 [Q532]