Keep some samples of plants consumed. In case of adverse reaction seek medical attention immediately, taking along the samples.

The information is given in good faith, but is by no means complete, and is of known hazards only. Absence of information on toxicity or danger is not indicative of a plant's safety. Consumption is at the reader's own risk and discretion.

Some guidance may reduce the risk of starvation in a survival situation, but it is best to err on the safe side when other food is available.

Take care identifying plants for consumption. In addition to visual characteristics, pay attention to habitat (including last year's dead stalks), season, smell (possibly crush a leaf) and feel. Always use a reputable field guide to identify wild plants. Plants may only be edible in part or after special treatment. Follow guidance.

Do not consume wild plants during pregnancy or with a medical condition, without consulting a health practitioner.

Only feed to minors if you are absolutely sure of the plant's safety. Where potential liver damage is indicated this is particularly pronounced in children.

Never follow any generalisation about what is supposed to be safe, only follow rules of avoidance.

Some individuals may react to some plants, which cause no ill-effect in others. Mis-identification can also happen, and when in a survival situation there may be no choice but to try unfamiliar plants. Always test a small amount first. Crush the part and first place on a sensitive part of the skin. Wait a moment to see if there is any reaction. If not, proceed to test on lips, then in the mouth, before finally swallowing a small amount. Wait for an hour or more to see if there is any reaction before consuming more.

Avoid touching unfamiliar plants if possible. Never touch food after touching unfamiliar plants.

Avoid plants which may have been sprayed with chemicals, which grow near heavy traffic and in public places with heavy foot traffic where dogs (even people) may soil them. When gathering plants from pasture with livestock, or in watercourses, wash and cook the plant well to avoid disease or parasites. Always wash plants well if eaten raw, wherever they come from.

Only pick good specimen. The breakdown products of dying or dead plant tissue may be toxic.

Eat a small amount of a wide variety of wild plants to get the best health benefit, and for greatest safety.

Avoid eating too many plants from the same family or with the same potentially harmful substance on the same day.

Yellow-flowered plants: leaves may give stomach upsets if eaten in quantity.

Red: this colour in a plant may signal danger. Follow caution notes.

Black, enlarged seeds on grasses: deadly ergot fungus.

Berries surrounded by 5 sepals: may be of the nightshade family (Solanaceae) and may be lethal, especially black, round berries.

Bulbs of some plants are toxic. Never eat a bulb from a dormant plant, unless you are absolutely sure of it's identity.

Pungent, unpleasant smell: often signals a poisonous plant.

Smell of almonds: may contain hydrogen cyanide.

Smell of fresh mown hay: may indicate coumarin.

Tastes extremely bitter: may contain hydrogen cyanide or other toxins.

Tastes extremely acrid: may be toxic.

Milky sap: may indicate toxicity. The latex of dandelions is mildly toxic, and can be consumed in moderation, but it would be advisable to remove the mid-rib of leaves, and not to consume the flower stems. Milky sap is often a skin irritant.

A stinging sensation in the mouth: if it is not a Stinging Nettle Urtica dioica this indicates protoanemonin, a substance found in all members of the buttercup family, or calcium oxalate. The irritating substance of the Stinging Nettle can be safely destroyed by drying or cooking, and is not protoanemonin or calcium oxalate.

Mouldy nuts: may contain the highly toxic aflatoxin.

Characteristics and Caution

Plant families often share similar characteristics and may contain the same or related substances, sometimes in different parts of the plant. They may also have other harmful characteristics like thorns or cause irritation on contact. When trying to judge the edibility of a plant which is not listed as edible it is best to assume common traits with close family members, especially genus. Only assume harmful traits. Individual species of families with no details given may still be harmful. See plant list for details on individual species.

This information should also be used to judge the quantity in which a plant may be consumed or what precautions may need to be taken if there is a likelihood that the plant contains a potentially harmful substance.

• Arum (Araceae): most or all are toxic, containing calcium oxalate in all parts. May also contain oxalic acid. The roots of some species may contain carcinogens.
• Balsam (Balsaminacea): some or all contain calcium oxalate in some parts. Seeds may be safe.
• Barberrry (Berberidaceae): the bark (especially of the root) of at least one species is toxic
• Bedstraw (Rubiaceae): contact with the sap of some species may cause irritation in sensitive people. The barbs of Cleavers Galium aparine can irritate the gastric tract if not softened by cooking. Sweet Woodruff Galium odoratum contains coumarin
• Beech (Fagaceae): some species contain tannin
• Bellflower (Campanulaceae): no information on hazards
• Bindweed (Convolvulaceae): some or all are toxic, probably mildly.
• Birch (Betulaceae): no information on hazards
• Bogbean (Menyanthaceae): at least one species can cause gastric upset.
• Bog Myrtle (Myriaceae): Bog Myrtle Myrica gale may cause abortion.
• Borage (Boraginaceae): some or all contain pyrrolizidine alkaloids. Some may cause contact dermatitis in sensitive individuals.
• Bur-reed (Sparganiaceae): no information on hazards
• Buttercup (Ranunculaceae): all are toxic, some can be eaten after special preparation, some are lethal, all produce protoanemonin in varying amounts.
• Cabbage (Brassicaceae): generally safe, though avoid mouldy leaves. Often spicy flavour. May depress the thyroid if eaten in quantity unless cooked or fermented (see lactofermentation on the Storage, Preparation and Poop page)
  
  
  Known hazards of individual species or genera:
  
  
  • Charlock Sinapis arvensis may be mildly toxic when seed pods form.
  • Hoary Cress Lepidium draba may be toxic.
  • Horseradish Armoracia rusticana can cause gastric upset and prolonged contact with the root can cause blisters.
  • Hedge Mustard Sisymbrium officinale may be toxic if consumed in quantity - may affect the heart.
  • The seeds of White Mustard Sinapis alba may be toxic (as pods form), and contact with them may cause dermatitis in sensitive people.
  • The oil of Rape Brassica napus seed is toxic unless from certain cultivars.
  • Wintercress Barbarea vulgaris may be toxic for kidneys. This plant can concentrate soil toxins. Only pick from uncontaminated land.
• Carrot (Apiaceae): there are a number of deadly poisonous plants in this family, with great superficial resemblance to edible plants. It is therefore advisable to be very careful when identifying plants in this family, and only consume them if you are completely sure of correct identification.
  
  Many contain furanocoumarin, found in higher concentrations especially in parsnip and celery, and may also be present in higher concentrations in their wild cousins. Only gather good specimens and consume as fresh as possible. Eat in moderation. Leaves, stems and flowers are often aromatic or pungent tasting. At least one member of this family will also cause severe blistering of the skin when coming into contact with the sap of the plant, and subsequent exposure to sunlight. Even the fine mist from cutting the stems may irritate the respiratory system. The introduced Giant Hogweed Heracleum mantegazzianum is very distinct when mature at 3.5m, but a young plant looks very similar to Hogweed H. sphondylium.
  
  Coriander Coriandrum sativum contains oxalic acid and may be narcotic if consumed in quantity.
• Cashew (Anacardiaceae): some members are toxic
• Cranesbill (Geraniaceae): no information on hazards
• Crowberry (Empetraceae): leaves of some or all may be toxic. The fruit of Crowberry Empetrum nigrum may cause nausea if eaten in quantity.
• Currant (Grossulariaceae): The leaves of Gooseberries Ribes uva-crispa and and Currants - genus Ribes, contain or produce hydrogen cyanide
• Cypress (Cupressaceae): Juniper Juniperus communis may be toxic to kidneys if consumed in large quantities. May contain thujone
• Daisy (Asteraceae): most are safe, but there are some toxic members. In the absence of information to the contrary, it is best to avoid any members of this family with a pungent smell.
  
  
  Known hazards of individual species or genera:
  
  
  • Members of the genus Senecio (e.g. Ragwort S. jacobaea and Groundsel S. vulgaris) and Tussilago (e.g. Coltsfoot T. farfara) contain pyrrolizidine alkaloids. Please note that Senecio jacobaea is the synonym of Ragwort. The appropriate botanical name is Jacobaea vulgaris, therefore the information may also apply to the genus Jacobaea.
  • Most thistles have sharp prickles which should be removed.
  • Burdock has irritating seed hairs.
  • Chamomile Chamaemelum nobile, Pineapple Mayweed Matricaria discoidea and Corn Marigold Glebionis segetum contain coumarin.
  • Stinking Chamomile Anthemis cotula can cause allergies in sensitive individuals.
  • Chicory Cichorium intybus may cause damage to the retina if consumed in quantity.
  • The latex of Dandelion Taraxacum officinale stems is a skin irritant.
  • The sap of Greater or Prickly Lettuce Lactuca virosa may be toxic and narcotic if consumed in quantity. Contains oxalic acid
  • Mugwort Artemisia vulgaris contains thujone. Contact with the plant may cause dermatitis in sensitive individuals.
  • Milk Thistle Silybum marianum may concentrate nitrates
  • Prolonged consumption of Yarrow Achillea millefolium may cause allergies. Leaves and flowers may also cause photosensitivity on contact. Contains thujone.
• Dock (Polygonaceae): most or all contain oxalic acid, some may cause photo sensitivity in sensitive individuals.
• Dogwood (Cornaceae): leaves and roots of Dogwood Cornus sanguinea are mildly toxic.
• Duckweed (Lemnaceae): no information on hazards
• Ferns and Bracken: some or most may contain carcinogens, and may also contain thiaminase.
• Figwort (Scrophulariaceae): at least one member is toxic (Foxglove Digitalis purpurea). Others may be mildly toxic, especially to the heart.
• Flowering Rush (Butomaceae): no information on hazards
• Fumitory (Fumariaceae): some or all may contain fumaric acid which is non-toxic and has a fruit-like taste.
• Gentian (Gentinaceae): no information on hazards
• Goosefoot (Chenopodiaceae): may contain saponins, and can accumulate nitrates and other toxins in the leaves. Only pick from uncontaminated land. Some also contain oxalic acid or produce hydrogen cyanide
• Grass (Graminae): some grasses contain coumarin. Any enlarged, black seeds are the highly toxic ergot fungus. Grass leaves often have sharp edges. The sap of Couchgrass Elytrigia repens may irritate skin of sensitive individuals. Edibility of rushes and sedges unknown.
• Hazel (Corylaceae): no information on hazards
• Heath (Ericaceae): some species have mildly toxic parts.
• Hemp (Cannabaceae): some are narcotic. Hop Humulus lupulus has irritating hairs and contains estrogenic substances which may interfere with hormonal therapy.
• Honeysuckle (Caprifoliaceae): some or all are toxic, at least in parts. Some contain saponins, some produce hydrogen cyanide
• Horse Chestnut (Hippocastanaceae): some or all contain saponins.
• Horsetail (Equisetaceae): some or all may be toxic, some mildly. May contain thiaminase. May contain equisetic acid, a potent heart and nerve sedative.
• Iris (Iridaceae): some or all are toxic, some in parts only, some are lethal.
• Lily (Liliaceae): some are toxic. Often sharp, pungent. Some contain saponins. Contact with the bulbs of some species may cause dermatitis in sensitive individuals. Onions are generally safe.
• Lime (Tiliaceae): older flowers of Lime Tilia vulgaris may be narcotic.
• Loosestrife (Lythraceae): no information on hazards
• Mallow (Malvaceae): most are safe, some may accumulate nitrates. Some are rare.
• Maple (Aceraceae): no information on hazards
• Mesembryanthemum (Aizoaceae): no information on hazards
• Mignonette (Resedaceae): no information on hazards
• Mint (Lamiaceae): some are toxic. Many look very similar - take care in identifying plants. Often aromatic. The essential oil of many is toxic and can cause abortions. Bugle Ajuga reptans has caused fatalities. Wild Clary Salvia verbenaca contains thujone.
• Mosses: edibility unknown, but doubtful.
  
  
• Mulberry (Moraceae): no information on hazards
• Nettle (Urticaceae): can accumulate nitrates and other toxins in the leaves. Only pick from uncontaminated land. Contact with plant causes irritation. Older leaves contain cystoliths, gritty particles - a kidney irritant. Irritating hairs contain formic acid and other irritants which are destroyed by cooking or drying.
• Nightshade (Solanaceae): most or all are toxic, some mildly, some in parts, some are lethal.
• Oleaster (Eleagnaceae): no information on hazards
• Olive (Oleaceae): contact with some plants may cause dermatitis in sensitive individuals.
• Orchid (Orchidaceae): safety for humans not known, but there is a danger to Orchids from harvesting, as many are rare. Many are protected by law.
• Pea (Leguminosae): some are toxic, especially the seeds. Some or all contain trypsin inhibitors.
  
  
  Known hazards of individual species or genera:
  
  
  • The seeds of members of the Vicia genus are toxic in quantity. Toxins may be removed by prolonged boiling and discarding the water.
  • White Clover Trifolium repens and Bird's-foot Trefoil Lotus corniculatus produce hydrogen cyanide when damaged.
  • Gorse Ulex europaeus has dense thorns.
  • Melilot Melilotus officinalis and Tall Melilot Melilotus altissimus contain coumarin.
• Pine (Pinaceae): bark, and possibly other parts may contain terpenes, volatile organic compounds, which are toxic in quantity.
• Pink (Caryophyllaceae): some or all contain saponins
• Plantain (Plantaginaceae): no information on hazards
• Poppy (Papaveraceae): most or all are toxic; probably all seeds are safe.
• Primrose (Primulaceae): the stamens of Cowslip Primula veris may cause alergic reactions. Some species, like the Scarlet and Yellow Pimpernel (Anagallis arvensis, Lysimachia nemorum) are toxic. Contact may also cause dermatitis in sensitive individuals.
• Purslane (Portulacaceae): no information on hazards
• Reed-mace (Typhaceae): no known hazards, but may be mistaken for poisonous plants.
• Rose (Rosaceae): very large and diverse family. Many have thorns. Most or all members of the genus Prunus (e.g. Plums) produce hydrogen cyanide, mainly in the leaves and seeds. Meadowsweet Filipendula ulmaria contains methyl salicylate, related to the drug Aspirin, and traces of coumarin
• Saxifrage (Saxifragaceae): no information on hazards
• Sea Lavender (Plumbaginaceae): no information on hazards
• Sedge (Cyperaceae): no information on hazards
• Spurge (Euphorbiaceae): some or all are toxic. Stems usually contain a milky juice.
• St. John's Wort (Clusiaceae): some or all may cause photosensitivity in sensitive individuals.
• Stonecrop (Crassulaceae):
  
  
  Known hazards of individual species or genera:
  
  
  • Orpine Hylotelephium telephium may be mildly toxic if eaten in quantity.
  • Contact with sap of Biting Stonecrop Sedum acre may cause irritation. Can cause gastric upset if eaten in quantity. May be toxic.
  • Reflexed Stonecrop Sedum reflexum can cause gastric upset if eaten in quantity. May be toxic.
• Teasel (Dipsacaceae): no information on hazards
• Valerian (Valerianacea): some or all are mildly narcotic and should not be consumed for more than three months at a time.
• Violet (Violaceae): no information on hazards
• Walnut (Juglandaceae): Cracked seeds are susceptible to dangerous moulds. They should be carefully stored.
• Water-lily (Nymphaeceae): some or all may be mildly toxic. Some are rare and protected by law.
• Water-plantain (Alismataceae): has toxic member(s)
• Willowherb (Onagraceae): some may be mildly toxic or irritant in part.
• Wintergreen (Pyrolaceae): no information on hazards
• Wood-sorrel (Oxalidaceae): most or all contain some oxalic acid. Wood-sorrel Oxalis acetosella also contains traces of calcium oxalates
• Yam (Dioscoreaceae): some or all are toxic. They contain saponins and calcium oxalates.

Calcium oxalate crystals cause severe irritation to mucous membranes and organs. These crystals, called raphides, are needle-shaped and cause a burning sensation in the mouth, sometimes after a brief delay, and may last for hours. They are also coated with a substance which causes swelling of the mucous membranes, which can cause suffocation. The substance may be destroyed by thorough cooking, but the raphides remain a severe irritant. It aggravates rheumatic conditions, kidney stones or hyper acidity. Severe poisoning can result in kidney damage and even death. May be destroyed by thoroughly cooking and steeping in several changes of water, however, any processing which removes the raphides will also remove most of the starch. Not worth the risk and best avoided.

Coumarin is a moderate kidney and liver toxin. It is present in greater quantities in dried plants. It can cause headaches and suppress appetite. Coumarin is transformed by certain fungi into an anti-coagulant, which may cause uncontrolled bleeding. Avoid if on drugs for circulatory conditions. Consume in moderation.
Coumarin smells of fresh cut hay and is present in Sweet Woodruff Galium odoratum, Sweet Vernal Grass Anthoxanthum odoratum, Melilot Melilotus officinalis, Mullein, Meadowsweet Filipendula ulmaria and some other sweet smelling greens, especially in the pea, grass and orchid families.

Furanocoumarin is produced by plants as a defence, especially when damaged or attacked by mould. May cause photodermatitis in contact with sap and exposure to sunlight or other ultra violet light. Only gather good specimen and consume as fresh as possible. Boiling can reduce it by half (discard water). Eat sparingly.

Hydrogen cyanide, also known as Prussic acid, may be safe in very small quantities. May be driven off by heat. Very bitter with smell of almonds.

Nitrates are linked with stomach cancer. Plants grown in nitrogen rich soil, especially grown with artificial fertiliser, can concentrate nitrates in the leaves. Avoid gathering plants where artificial fertilisers are used, or near farm yards, dung heaps and other nitrogen rich places.

Oxalic acid can bind up other minerals, especially calcium. May aggravate rheumatic conditions, kidney stones, hyper acidity or osteoporosis. May be reduced by cooking, possibly also if eaten with a source of salts derived from methyl salicylate (salicylic acid etc.) from sources such as dried Meadowsweet Filipendula ulmaria. May also be bound by calcium eaten at the same time to form large molecules which can not be absorbed but will be excreted. Eat in moderation.

Protoanemonin is a toxin produced by all species of the buttercup family (Ranunculaceae) family in varying quantities when damaged. Contact may causes itching or blistering. In the mouth it causes a burning sensation, and ingested causes gastric upset, headache, dizziness, spasms, paralysis or circulatory failure. Protoanemonis is non-cumulative and may be destroyed by heat and drying.
Some species of buttercups are highly toxic.
Take extra care identifying, handling and preparing plants in this family

Pyrrolizidine alkaloids can cause liver damage and cancer and are cumulative. Best avoided.

Saponins may be beneficial in small doses, but are toxic in large. Toxicity varies amongst the different types of saponins. May be removed by leaching, rinsing or heat. Eat in moderation. May affect mucous membranes. Some saponins are highly toxic.

Tannin binds with protein, can interfere with iron absorption and can cause gastric pain, irritation to organs and liver damage. It is bitter and astringent and colours water dark. It may be reduced or removed by leaching in several changes of water, until it runs clear (not brown). Baking soda added to the water may speed up the process. Tannin breaks down with time. It may also be reduced or destroyed by lactic fermentation.

Thiaminase is a heat-resistant enzyme which destroys Vitamin B1. It is safe in small quantities, and when the diet contains plenty of Vitamin B1. It is destroyed by cooking at 80 degrees Centigrade or above for at least 5 minutes.

Thujone is toxic to brain and liver cells and may cause abortion if consumed in quantity. Avoid if pregnant.

Trypsin inhibitors interfere with protein digestion and are reduced or destroyed by sprouting.