Horseweed

Basic Information

Scientific Name: Erigeron canadensis (syn. Conyza canadensis)

Plant Family: Asteraceae

Conservation / Invasive Status: Not Evaluated

Geographic Range: Native to Northern New England

Safety Level: Generally Safe

Harvest Season: Late summer through fall (seeds), Summer through early fall (aerial parts)

Parts Used: Aerial Parts, Flowers, Leaves, Roots, Seeds

Scientific & Botanical Information

Active Compounds

Contains volatile oil, tannins, flavonoids, phenolic compounds. Key constituents include limonene, p-cymene, and myrcene in the essential oil. Traditionally valued for respiratory support.

What Science Shows

Traditional respiratory support agent. Modern research limited but supportive of traditional use patterns. Mechanisms likely involve volatile oil action on respiratory tissues and antispasmodic properties of tannins.

Growing in New England

Found throughout New England as common annual/winter annual. Prefers disturbed areas, fields, and waste ground. Can be prolific in suitable habitat. Traditional preparation involved aerial parts harvested mid-season.

Safety & Interactions

Well-tolerated traditional use. No significant contraindications reported. Mild diuretic properties suggest caution in severe fluid loss. Volatile oil content suggests respiratory benefits but not for prolonged internal use without practitioner guidance.

New England Specific

Common New England weedy annual with long history of traditional use. Readily available for bioregional herbalism applications. Historic use documented in New England ethnobotanical records.

Pharmacological Actions: Anthelmintic, Anti-inflammatory, Anticancer, Anticoagulant, Antifungal, Antimicrobial, Antioxidant, Astringent, Diuretic, Hemostyptic

Traditional Herbalism Information

Parts Used & Their Applications

Aerial parts (stems, leaves, flowers) harvested when plant in bloom. Traditionally gathered in mid to late summer when oil content peaks. Entire above-ground plant used, collected before seed maturation.

Preparation Methods

Dried herb prepared as infusion (steep 5-10 minutes, 1 teaspoon per cup), stronger decoction (simmer 10 minutes), or fresh plant tincture (alcohol extraction). Some traditions favor infusion for volatile oil preservation.

Traditional Applications

Native use for respiratory conditions and general respiratory health. Mild diuretic noted in traditional preparations. Settlers incorporated into respiratory formulas and teas. Traditional preparation for seasonal respiratory support and ease.

Modern Adaptations

Contemporary herbalists employ in respiratory blends alongside other respiratory-supporting plants. Used in tea mixtures for seasonal respiratory support. Occasionally included in tincture formulas for respiratory conditions. Valued for common availability and traditional efficacy record.

New England Specific

Commonly available wild plant providing accessible respiratory support. Self-sowing in disturbed soils makes it readily harvestable. Represents New England tradition of using abundant native weeds medicinally.

Harvest Notes

Aerial parts best harvested June-August when in bloom and oil content high. Aerial parts best harvested mid to late summer. Can be used fresh or dried for storage.

Traditional Uses: Diarrhea and dysentery treatment, Diuretic Support, Fever Reduction, Hemostatic (bleeding disorders), Respiratory Support, Wound Healing

Magical Correspondences Information

Magical Correspondences

Planetary: Mercury. Elemental: Air. Traditional associations: mental clarity, communication, swift movement, journeying.

Magical Intentions

Employed for mental clarity and focus. Air association supports journeying work and communication magic. Swift growth pattern reflects quick manifestation. Used in workings for clarity of thought and rapid change.

Ritual Uses

Burned as incense for clarity and communication enhancement. Carried for mental sharpness. Used in travel magic and messaging spells. Placed on altar for Mercury workings and intellectual pursuits.

Color Correspondences

Green (growth, vitality), yellow (clarity, communication), white (purification and new beginnings).

Sabbat Associations

Imbolc (new beginnings), Beltane (swift growth), Lammas (quick harvest), Mabon (gathering and preparation).

Traditional Lore & Folk Magic

As common weed, included in folk magic traditions. Swift growth and prolific nature symbolized rapid change and adaptability in magical work.

Combining with Other Plants

Pairs with mullein for respiratory support in magical working. Combine with mint for clarity enhancement.

Planetary Rulers: Mercury

Magical Intentions: Adaptability, Cleansing, Communication, Mental Clarity, Purification, Quick Action

Elemental Associations: Air

1 Moerman, D.E. (1998). Native American Ethnobotany. Timber Press.
2 Mills, S. & Bone, K. (2005). The Essential Guide to Herbal Safety. Elsevier.
3 Hoffmann, D. (2003). Medical Herbalism: The Science and Practice of Herbal Medicine. Healing Arts Press.
4 Peterson, L.A. & McKenny, M. (1968). A Field Guide to Wildflowers. Houghton Mifflin.