Black Walnut (Juglans nigra)

Black Walnut (Juglans nigra) is a member of the Rhoipteleaceae family, native to Eastern North America, United States, and Eastern United States. Traditionally, its seeds, bark, and fruits have been used for decoctions, infusions, and poultices.

This herb is particularly valued for its anti-inflammatory, tonic, and bitter actions, and has a long history of use in native american herbal medicine, european herbal medicine, and traditional chinese medicine.

Black Walnut (Juglans nigra) dried pieces of the herb arranged on a wooden table for reference — Black Walnut (Juglans nigra) dried pieces of the herb arranged together on a wooden table for reference, used in teas and remedies.

Quick Facts / Key Information

Common Name	Black Walnut
Scientific Name	Juglans nigra
Plant Family	Rhoipteleaceae
Genus	Juglans
Species	nigra
Native Range	Eastern North America, United States, Eastern United States
Plant Parts Used	Seeds, Bark, Fruits
Primary Medicinal Actions	Anti-Inflammatory, Tonic, Bitter
Primary Traditional Systems	Native American Herbal Medicine, European Herbal Medicine, Traditional Chinese Medicine
Historical Preparation Methods	Decoction, Infusion, Poultice

Botanical Identity

Scientific Name: Juglans nigra
Common Name: Black Walnut
Synonyms / Alternative Names: Black Walnut Tree, American Black Walnut, American Walnut
Plant Family: Rhoipteleaceae
Genus: Juglans

Botanical Description

Growth Habit: Perennial woody plant.
Height: It typically reaches a height of 10 to 20 meters.
Leaves: Simple leaves with doubly serrated margins, upper surface dark green, lower surface pale green, bearing prominent stomatal bands along the midrib.
Flowers: Flowers are solitary, actinomorphic, with yellow-green petals and a distinctive heart-shaped stigma.
Stems: Elongated, erect growth habit with opposite branching, smooth, glabrous surface, and persistent, ridged bark with longitudinal lenticels.

Traditional Uses / Historical Use

Traditional Systems

Native American Herbal Medicine
European Herbal Medicine
Traditional Chinese Medicine
Japanese Kampo Medicine

Historical Preparation Methods

Decoction
Infusion
Poultice
Powder

Medicinal Actions

Anti-inflammatory: Traditionally described as a gentle anti-inflammatory, for general calming applications.
Tonic: As described in traditional systems, a calming tonic, for broad-use formulations.
Bitter: Commonly referenced as a mild bitter, in appetite-focused contexts.
Diuretic: Historically regarded as a warming diuretic, for moisture-related balance.

Active Compounds

Flavonoid: Naturally occurring polyphenols that contribute to pigmentation and structural chemistry.
Tannin: Naturally occurring polyphenols widely distributed in woody and leafy plant parts.
Phenolic Acid: Organic acids commonly occurring as part of plant secondary metabolism.
Saponin: Plant-derived compounds characterized by their soap-like properties.

Modern Research Overview

Contemporary research on this plant includes areas such as chemical analysis, laboratory-based studies, and observational research. Detailed summaries of published findings are not included at this stage and will be added during future content updates.

Safety & Contraindications

General Precautions: Caution is advised in certain contexts based on traditional use and available information.
Contraindications: Available information does not clearly establish contraindications for the use of this herb.
Allergies: Allergic reactions associated with this herb have not been well documented.
Drug Interactions: The potential for interactions with prescription medications has not been extensively studied.
Toxicity: Toxic effects have been reported in association with the use of this herb.
Pregnancy & Breastfeeding: Safety during pregnancy and breastfeeding has not been well documented.

Preparation & Usage Methods

Infusion: Water is poured over plant material and allowed to steep before straining.
Decoction: Plant material is simmered in water to extract compounds from tougher parts.
Poultice: This method uses direct contact between plant material and the skin.
Powder: Plant parts are dried and mechanically reduced to a powdered form.
Culinary Use: Plant material is incorporated into food or beverages for flavor or aroma.

Growing, Harvesting & Storage

Growing / Cultivation

Soil: Prefers loamy soil with moderately well-drained conditions. Typically grows best in organically rich soils.
Sunlight: Thrives in full sun. Tolerates full sun to partial shade.
Watering: Prefers seasonally moist soils. Tolerates periodic dry conditions.