Materia Medica: Black Walnut Leaf
Société Apothecary
Black Walnut Leaf: Materia Medica Strong, bitter, and deeply cleansing, Black Walnut Leaf has long been valued in North American and European herbal traditions for its purifying, astringent, and antifungal properties. While the hull is better known, the leaf holds its own as a cooling, toning remedy—especially for skin, parasites, and excess heat. “Black Walnut leaf cuts through the murk—cooling, cleansing, and clarifying inside and out.” MATERIA MEDICA Latin Binomial: Juglans nigra Common Name(s): Black Walnut, Eastern Black Walnut TCM Name: Not commonly used Ayurvedic Name: Akhrot patra (related walnut leaves) Family: Juglandaceae Physical Description of the Plant: A large deciduous tree with deeply ridged bark, pinnate compound leaves with 15–23 leaflets, and round green fruit encasing a hard nut. Leaves are aromatic when crushed. Habitat: Native to eastern North America. Grows in well-drained soils, forest edges, and river valleys. Harvest and Collection: Leaves are harvested in summer before they turn yellow. Best when fresh or recently dried, as they lose potency over time. Parts of the Plant Used: Leaves (occasionally used fresh; often dried) Qualities: Bitter, astringent, slightly aromatic Energetics: Cooling, drying, purifying Chemical Constituents: Tannins Juglone (a naphthoquinone compound) Flavonoids Volatile oils Vitamin C and chlorophyll (in fresh leaves) Actions: Astringent Antimicrobial Antifungal Antiparasitic Anti-inflammatory (mild) Alterative (cleansing and blood-purifying) Lymphatic tonic (gentle) Indications: Skin conditions: eczema, acne, psoriasis Fungal infections: athlete’s foot, ringworm Intestinal parasites (as part of protocols) Diarrhea and dysentery Weepy, inflamed skin or rashes Mouth and gum inflammation (as rinse) Diagnostic Picture: Black Walnut leaf is best for hot, damp, irritated conditions—externally or internally. It cools inflamed tissues, tones mucous membranes, and helps resolve persistent skin and GI complaints with a cleansing, bitter edge. Contraindications/Cautions: Avoid in pregnancy and while breastfeeding Avoid in large doses or long-term use due to potential juglone sensitivity Use with caution in dry constitutions—can exacerbate dryness Not for open or deep wounds externally Drug Interactions: May interact with laxatives or antifungal drugs (synergistic or potentiating effects) Avoid with immune-suppressants in autoimmune cases Dosage: Infusion (Tea): 1 tsp dried leaf per cup; steep 10–15 min; up to 2–3x daily Tincture: 1–2 mL, 2x daily (short term use only) Topical Wash/Compress: Strong infusion or diluted tincture applied to affected skin Mouth Rinse: Weak infusion for gum inflammation or sore throat Combinations: With Calendula or Plantain for skin rinses With Wormwood and Clove for parasite protocols With Burdock and Yellow Dock for chronic skin detox With Yarrow for astringent skin formulas Folklore: Black Walnut was used by many Native American tribes for parasite cleansing, skin conditions, and ceremonial purification. The