POISONOUS PLANTS

This section deals with those plants we must be extra careful to avoid, since it is very easy when wildcrafting to mistake one plant for another, and sometimes this can have dire consequences. Garden plants and poisonous plants already mentioned have not been included.

Apiaceae Family

Plants in this family are tricky to identify and include edible plants like carrot, Queen Anne’s Lace, parsnip, parsley, fennel, and dill. However, there are others that can be extremely toxic and that closely resemble their edible relatives—particularly the flowers, which are usually white and in clusters arranged in umbels or umbrella-like formations. These plants contain chemicals in their sap which can cause phytophotodermatitis on the skin if touched. A good rule is: if you’re not 100% sure what a plant is, leave it alone!

treatment

If you accidentally touch any of these plants, immediately keep your skin away from sunlight and wash the area with cool running water. Avoid rubbing or using hot water, as this will open the pores and allow the poison to go deeper. Use a mild soap to remove any remaining residue. If there is soreness, cover the area with a cool, damp cloth. If there are open sores or blistering, apply an antibiotic cream and sterile bandage, taking care to change the bandage at least twice a day. If a large area is affected, consult your doctor.

COW PARSNIP

Heracleum maximum

  • Native, grows in a variety of habitats.
  • Grows up to 2 metres.
  • Flower umbels up to 30 cm. diameter, white.
  • Leaves can be almost 60 cm. wide, hairy, and divided into 3 deeply lobed leaflets. Lobes are more rounded than those of Giant Hogweed.
  • Stem does not have purple blotches like the Giant Hogweed.
  • Contains furanocoumarins, which cause phytophotodermatitis, especially older plants.

WILD PARSNIP

Pastinaca sativa

  • Introduced, invasive, grows in disturbed areas, meadows.
  • Grows up to 1.5 metres.
  • Single green stem is smooth with few hairs and deep grooves.
  • Compound leaves in pairs; sharply toothed leaflets resembling celery.
  • Flowers are yellow-green and grow to 10–20 cm. across, resemble dill and fennel; single stalk with flat-topped umbel.
  • Roots are edible, however great care must be taken to not touch the leaves or stalk with bare hands.

FOOL’S PARSLEY

Aethusa cynapium

  • Introduced, annual or biennial.
  • Hairless, smooth hollow, branched stem, up to 150 cm. in height.
  • Leaves alternate, 2 or 3 times pinnate, triangular, similar to parsley but with a foul onion-like smell.
  • Root shaped like a spindle, and tapered at each end.
  • Flowers are white and appear in flat umbels; distinctive characteristic is 3 bracts or appendages hanging from each cluster.
  • Dangerous if mistaken for parsley and ingested, for it contains poisonous alkaloids that cause burning in the digestive tract, vomiting, coldness, and even death.

GIANT HOGWEED

Heracleum mantegazzianum

  • Introduced, invasive, after 3–5 years can grow up to 5 metres high.
  • Umbels are white and can be half a metre across, with over 50 rays.
  • Stems thick, ridged, and hollow, with purplish blotches and stiff white bristles.
  • Large lobed compound leaves with deep incisions and serrated edges.
  • Causes severe phytophotodermatitis.

POISON HEMLOCK

Conium maculatum

  • Introduced biennial, invasive, 2–3 metres tall, grows near streams and in ditches.
  • Stems hairless, hollow, usually spotted with red or purple towards the base.
  • Leaves are 2–4, pinnate, finely divided, triangular, and similar to a carrot’s. When crushed, they emit a musty smell.
  • Flowers are white and grow in loose clusters.
  • All parts of this plant are poisonous; causes severe skin reactions, and when ingested can affect the nervous system, cause respiratory collapse, or even death.

WATER HEMLOCK

Cicuta maculata

  • Native perennial, .6 to 1.8 metres tall. Grows in wet areas.
  • Stems are erect, mostly hollow, reddish-purple, and mostly hairless.
  • Lance-shaped leaves, 2–3 times pinnate with a single leaf at the tip, coarsely toothed, with lateral veins that extend to notches between the teeth.
  • Roots are fleshy, tuberous, chambered, and hollow. The yellow oily sap exuding from stem and root is foul-smelling.
  • Flowers are whitish-green, with dome-shaped umbels.
  • Contains cicutoxin; even small doses of the sap are lethal, causing convulsions and respiratory failure within a few hours.

Other Species to Avoid

BUTTERCUP (all species)

Ranunculus

  • Small perennial, about 500 species.
  • Lustrous yellow flowers, cup-shaped, usually 5 petals.
  • All species are poisonous if eaten fresh. The plant has an acrid taste and causes blistering in the mouth and digestive tract, bloody diarrhea or urine, and abdominal pain.
  • Avoid excessive handling as it may cause contact dermatitis.
  • When dried, buttercups lose their toxicity.

HEMP DOGBANE (INDIAN HEMP)

Apocynum cannabinum

  • Native perennial resembling Milkweed. Identify Hemp Dogbane by its red stem, often branched, and smaller cluster of whitish flowers, smaller narrower leaves, and narrow seedpod.
  • Grows up to 1.8 metres tall; used by Indigenous peoples to make fibre for ropes and clothing.
  • Leaves are elliptical, opposite, with light-green veins.
  • Flowers are small, cylindrical, and greenish-white; milky white sap in stems and leaves.
  • Contains cardiac glycosides and cymarin; consumption in humans and animals may cause rapid pulse, vomiting, blue mucous membranes, weakness, convulsions.
  • Treatment suggestions in animals include emetics or activated charcoal. Humans who have been poisoned should seek immediate medical help.

BITTERSWEET NIGHTSHADE

Solanum dulcamara

  • Vine-like non-native perennial, grows up to 3 metres tall.
  • Alternating heart-shaped leaves, with 2 ear-like segments at the base.
  • Star-shaped purple flowers, with bright yellow stamens in the middle. Mature berries are bright red.
  • Berries are toxic, and eating more than 200 is considered lethal. Particularly attractive to children as they taste a bit like tomatoes. Symptoms include diarrhea, dilated pupils, headache, vomiting, paralysis, convulsions.
  • Treatment: an emetic should be administered, along with fluids.

POISON IVY

Toxicodendron radicans

  • Almond-shaped leaves, which are sometimes toothed, sometimes shiny, growing in groups of 3, ranging from light green to dark green, to reddish in the fall. Leaf clusters alternate on the vine, growing close to the ground or attaching to trees.
  • Mainly allergenic rather than a poison, the sap contains urushiol, which causes a severe allergic reaction in most people when handled, resulting in contact dermatitis, itching, and blistering. Ingestion may cause stomach upset, but is not severe.
  • Treatment: wash exposed area immediately with soap and cool water for 30 minutes; avoid spreading the oils to other parts of the body. Symptoms may be relieved by rubbing Jewelweed on the skin, applying calamine lotion, witch hazel, zinc oxide, or taking an oatmeal bath.

POISON SUMAC

Toxicodendron vernix

  • Sparse shrub, 1.5–6 metres tall, with red stems. Thrives in wet soil, and found only in Nova Scotia and Quebec.
  • Pinnate structure with 6–12 leaves growing on each side of the stem, with 1 more at the end. Each leaf is 5–10 cm. in length, almond-shaped, with wavy or smooth edges. Leaves may be orange or light green in the spring, green in summer, and red during the fall.
  • Pale yellow or green flowers grow in clusters on stems separate from the leaves. These grow into green, yellow, or grey-white berries.
  • Treatment is the same as for Poison Ivy.

POKEWEED

Phytolacca Americana

  • Native perennial, usually up to 2 metres high, and found only in New Brunswick and Quebec.
  • Several stems growing out of a central taproot; stems are smooth, green to reddish, and the leaves are alternate with long petioles.
  • Flowers grow in elongated racemes with bright-pink peduncles. The clusters of flowers are radially symmetric and white or greenish. Ripe berries are shiny dark purple.
  • All parts are toxic to mammals, but not to birds. A violent emetic, Pokeweed causes cramps, bloody diarrhea, and/or paralysis of respiratory organs, depending on amount consumed. Plant juice may also be absorbed through the skin. If only ingested in a small amount, people or animals will recover in a day or two.