Photo: Krzysztof Ziarnek, CC BY-SA 3.0, Wikimedia Commons

Fool's Parsley

Aethusa cynapium

Poisonous

A garden weed that grows among real parsley and causes burning, vomiting and collapse.

Educational content, not medical or professional advice. In an emergency call your local emergency number (112 in Europe) first. Never eat a wild plant or mushroom because of a website or photo.

⚠️ Suspected poisoning needs a call to emergency services on 112, or to the CIAV poison line in Portugal, or your own country's poison service. Do not wait to see how bad it gets.

⚠️ Keep a sample or a photograph of the plant for the hospital.

⚠️ Do not induce vomiting unless instructed by a professional.

⚠️ Sap can irritate skin. Wear gloves when weeding it out.

⚠️ Children and pets are most at risk because it grows exactly where family vegetables grow.

⚠️ Weed it out of any bed where you grow parsley, coriander or carrots before it can be picked by mistake.

Confused with

Flat-leaf parsley (Petroselinum crispum)

Danger: Burning of the mouth and throat, severe vomiting and diarrhoea, dizziness, and in serious cases paralysis and seizures. Deaths are rare but have happened, especially in children.

How to tell: Turn the flower head over. Fool's parsley hangs three to five long narrow bracts beneath each little umbel like a drooping beard. Parsley has none. Before flowering, crush a leaf: parsley smells clean and green, fool's parsley smells sharp and foul.

Chervil and young wild carrot leaves

Danger: Same burning gut poisoning, easily mistaken for a bad stomach bug so treatment is delayed.

How to tell: Chervil leaves are softly hairy and smell of aniseed. Fool's parsley is hairless and smells foul. Hairiness plus smell together is the check to make.

Leaves

Dark green, glossy, triangular in outline, divided two or three times into narrow pointed segments, hairless. Alternate. They look very like flat-leaf parsley but are shinier and more finely cut, and the underside has a slight greyish sheen.

Flowers

Small white umbels 2 to 6 cm across. The giveaway is under each small umbel: three to five long narrow green bracts hang downward like a little beard on the outer side only. No other white umbellifer of this size does that.

Stem

Hollow, hairless, finely ridged, green and sometimes faintly purple at the base but without hemlock's bold blotches.

Smell or taste

Crushed leaves smell unpleasant, sharp and slightly of garlic or rotting foliage, quite unlike the clean smell of parsley. Do not taste it to check.

Habitat

Cultivated ground, vegetable gardens, allotments, arable fields, disturbed soil and compost heaps. It is a weed of the very beds where parsley is grown, which is the whole danger.

Preparation

No preparation makes it safe. Cooking reduces nothing reliably. The safe rule is simpler than any test: do not gather parsley-like leaves from the wild or from a weedy bed. Grow your parsley in a clean, weeded container you control.

Traditional use

Occasionally listed in old herbals as a sedative for children's digestive complaints. That use caused poisonings and has been abandoned. Do not repeat it.

Harvest rule

Remove, never harvest. Gloves on, pull before it sets seed, bag it rather than composting it beside salad beds. Do not burn it with garden waste you will stand over. Keep children and poultry off the bed until it is cleared.

Salsa-dos-tolos, cicuta-menor (PT); lesser hemlock (EN)