Astragalus

Astragalus is a sweet-tasting root from the Fabaceae or Pea Family.  In Traditional Chinese Medicine, it's considered a Spleen Qi and a Lung Qi, which means it can help improve appetite and digestion as well as boost the immune system to help strengthen those who are prone to colds and flu.  

Energetically, it's moist and warming, but may be a little drying.

This herb has cautions for those taking immunosuppressive or blood pressure medications, or Lithium or Cyclophosphamide.