Type of plant: Slow-growing evergreen conifer tree growing to 60 feet with blue-green needles and small purplish seed cones

Part used: Twigs and needles

Method of extraction: Steam distillation

Data: Native throughout Canada. The branches exude an edible gum — the source of spruce gum, the original American chewing gum first sold commercially in the early 1800s. It was introduced to the colonists by people of the First Nations, who also showed how the gum could be used to heal wounds. They also used the needles to make spruce beer, which can be alcoholic or nonalcoholic, to alleviate scurvy during the long winter months when fruits weren’t available.

Principal place of production: Canada

When buying look for: A colorless to yellow-tinged liquid with a sweet, fresh, woody, resinous, fruity, green aroma

Therapeutic properties: Anthelmintic, analgesic, antibacterial, antifungal, anti-inflammatory, antispasmodic, diuretic, expectorant, insect deterrent, pectoral

Therapeutic uses: Bronchial infection, catarrh, sinus congestion, arthritis, rheumatism, gout, overexercised muscles, stiff joints, muscular strain, tendonitis, cellulite

Blends well with: Bay laurel, camphor (white), cedarwood, chamomile german, cypress, geranium, lavandin, lavender, lavender (spike), lemon, niaouli, orange (sweet), peppermint, pine, ravintsara, rosemary, spearmint, tea tree, thyme linalol, yarrow

Precautionary advice: May cause irritation on highly sensitive skins; a skin patch test is advisable. Best avoided during pregnancy.