Used in cases of exhaustion, food allergy or depression, and to improve digestion, and eliminate excess fluids. In his book Healing Lyme Stephen Harrod Buhner claims that astragalus can prevent and treat the many and varied symptoms of Lyme disease. Small yellow pea-like flowers on upright stems with vetch-like leaves. 1½–4' perennial. Plant in deep well-drained slightly alkaline soil. Harvest 4-6 -year-old roots in fall. Zone 4.