Water hemlock dropwort – Oenanthe crocata. A Forager’s photo guide

Could you confidently identify the deadly water hemlock dropwort ? Introducing a deadly poisonous plant - water hemlock dropwort

Key features to know when identifying water hemlock dropwort.

Water hemlock dropwort is one of the most important plants for foragers to know well, and I mean really well! Your foraging safety may depend on you knowing this and the other relatively few deadly poisonous plants that you are likely to come across when foraging.

Water hemlock dropwort is an umbellifer and all of the umbelliferae produce compound umbel flowers,
Water hemlock dropwort showing its faily pattern of a compound umbel flowers

Read on for botanical descriptions, photographs and videos to help you identify water hemlock dropwort. It’s a really common plant, and if you are anywhere near water, it’s one that will be found throughout the year, unless covered in snow.

If you are interested in foraging from the carrot family, and to be fair, it’s almost inevitable that you will be if you have fallen in love with wild foods, then it will  become absolutely necessary to know this plant, alongside it’s look-a-like relatives. This  will probably require careful and repeated study, at all stages of its growth, and often with the passing of a couple of years.

In my previous post, you could learn about the exciting Apiaceae family, a.k.a the umbellifers. The key umbellifer plant patterns can be learnt quickly and easily, and  it’s possible to practise them almost anywhere.

The tell-tale ‘birds nest’ seed head from a  different umbellifer – wild carrot (Daucus carota)

Umbellifers are extremely common – an absolute staple of the countryside, and have therefore found homes all over our towns and  cities as soon as we moved in.

Leaf shapes and arrangements amongst umebllifers can be similar, as a close relative of water hemlock dropwort shows.
The remarkably similar leaf from a close relative Oenenathe pimpinilloides (Corky-fruited dropwort)

Aside from the half dozen or so close relatives in the genus Oenanthe (some also reportedly poisonous but not deadly), water hemlock dropwort has a couple of edible plants that it superficially resembles, and one plant that it’s almost a dead ringer for at first glance!

The look-a-likes often happen to live side-by-side in favourite habitats, so all the more reason for proceeding with caution.


Key features to look out for when identifying water hemlock dropwort.

Luckily for the budding forager, Water hemlock dropwort is easy to find! Pop down to almost any watercourse in Britain and you should come across it’s lime-green foliage. During the winter months it can be found growing happily away with basal rosettes of leaves. With so many other plants dormant, you should find it easier to spot during the darkest days of mid-winter.

As long as you are remembering to re-visit patches and plants through the seasons then you will get to know the plant.  Understanding a plant’s refinement in form as it develops to produce a flowering stem, will mean you are ready for the changes in appearance that this plant produces.

Botanical an Photographic guide to water hemlock dropwort (Oenenathe crocata).

  • Water-loving herbaceous perennial

  • Shiny, triangular, pinnate leaves, 3-4 times divided with oval – lanceolate leaflets


  • Water hemlock dropwort can grow in excess of  1 m 50 cm across  and 1 m 5o cm high 


  • The plant ‘over-winters’ by watercourses, so can easily be spotted

  • Leaflets with deeply cut toothed margins


  • Celery / Parsley scented herb



  • Petiole solid, with spongy pith, occasionally with white latex



  • Petiole sheath at the base
  • Petiole a flattened cylindrical-shape, with fine ridges


  • Hollow, cylindrical flowering stems, with fine grooves



  • White compound umbels, individual umbels displayed like pom-poms



  • Umbels 10-20 cm with many rays


  • Bracts and bracteoles are small linear, and will wither


  • Tiny (2 mm) pom pom white flowers with unequal petals and tiny red anthers in the flower



  • Fruits 4-6 mm, cylindrical, ridged




  • Fat, oval-spindle shaped tuberous roots.

Favourite habitats of water hemlock dropwort

  • marshes and moist ground

  • wet woodlands and woodland clearances

  • brooks, streams, riverbanks and canalsides


Edible parts

None of course!All parts of this plant are deadly poisonous – One bite of the root is apparently sufficient.

Wild celery is one of the look alikes of water hemlock dropwort
Wild celery (Apium graveolens) Note the singular pinnate leaf division.

Lookalikes – Other water-dropwort Oenanthe species, wild celery (Apium graveolens), alexanders (Smyrnium olusatrum), and wild angelica (Angelica sylvestris).

The look alike alexanders has leaflets in sets of threes, yellow flowers, and has a different smell.
Patches of alexanders (Smyrnium olusatrum) will be found by the coast, sometimes near to water hemlock dropwort. Alexanders has leaflets in sets of threes and a different smell.


Leaflets are oval on wild angelica rather than serrated with divisions and leaflet lobes, as found on water hemlock dropwort
Wild angelica (Angelica sylvestris) has oval leaflets, often with purple tinges. Also found by riverbanks and in damp woodlands


Wild angelica leaflet, showing the regular serrations. Note they are without the leaflet divisions found on water hemlock dropwort

A quick video with water hemlock dropwort


Geographic distribution of water hemlock dropwort

Abundant SW England and Wales. Common West Scotland. Rarer to absent oN the drier soils of East England, the Midlands, and NE England. Check out the online flora for a map and other information

Now you have the photos, video’s and descriptive information, you shouldn’t ever be as reckless and ignorant as the foolish and ever so fortunate campers up in Argyll, Scotland.

If you would like to get to know the carrot family more, you can book on one of my regular foraging events, which include carrot family courses, or try my article on getting to know the carrot family, available here.

Stay safe, happy foraging!

Foraging St John’s wort

Hypericum perforatum  (St Johns wort)

Hypericaceae family

This summer-flowering medicinal plant grows wild and free throughout many areas of Britain. With a liking of numerous settings it will be easy for foragers to find St John’s wort, and with unique observable characteristics, it is simple to identify. You can find out more about plant identification on my foraging walks and courses.

The scientific name for the genus, Hypericum, is thought to originate from the two Greek words – hyper, meaning above, and eikon, meaning ‘picture’.

The bright yellow flowers, which many centuries ago were felt to be symbolic of the sun, or spirit, were placed above religious pictures, specifically St John, to help ward off evil spirits during the celebrations of the midsummer Christian festival. Church leaders placed their festival onto the ancient summer solstice festivities (since the introduction of the Gregorian calendar, this has traditionally been celebrated on 24th June, previously falling on or around the 5th July).

The extractable red flower oil was previously meant to symbolize the blood of St. John. The species name perforatum is derived from the Latin word meaning perforated. Visible translucent perforations on both the leaves and the petals are visible with the naked eye.

The blood red stems of young spring growth on Hypericum perforatum.

Botanical description of St John’s wort

St Johns wort is a native British perennial, from a genus containing over 400 species of annuals, herbaceous perennials; deciduous, semi-evergreen and evergreen shrubs and trees. This plant grows throughout Europe.

St Johns wort is a clump-forming perennial which can grow to a height of up to 90 cm in flower. Re-appearing each year from its crown, it produces numerous red stems that eventually branch towards their upper parts. The stems bear small and hairless leaves, which are opposite and mostly oblong, but always sessile. The leaves typically grow to 3-4 cm long.

If you hold the stems up to the light, close inspection will reveal the leaves have numerous translucent glands, as well as a few dark ones at the edges on the undersides. The lanceolate petals and shorter sepals in the flower are also marked with dark dots.

The presence of the dark oil bearing glands, as well as the slight, opposite ridges on its round stem are crucial identification factors between this and one of more than half a dozen other Hypericum species that populate Britain.

The bright, glossy yellow flowers are similar in size to a buttercup. They have five petals and are borne on a corymb inflorescence. These types of flowering displays are often referred to as umbel-like.

When in full display, the shiny, showy blooms are noticeable for having more than fifty stamens spraying out from the centre of the flower. These are fused in the lower part into three bundles.

Hypericum perforatum flowers

Flowering Period

The flowering period for this plant is usually lengthy, and occurs between June and September, with the seeds ripening from late July to October. The self-fertile flowers are pollinated by bees and flies.

Soils and Habitats

St Johns wort absolutely delights on calcareous (alkaline) soils, as will be seen by the propensity of it when visiting chalk grasslands such as around Winchester and in West Sussex on the South Downs. It’s not a completely fussy plant, so will also be found on mildly acidic ground.

It can do well on waste-ground and some woodland edges, and is often seen happily populating pastures, as well as roadsides and occasional hedges. This is a lowland plant, so will be found at maximum altitudes up to around 480 metres.

St Johns wort can grow in the semi-shade of light woodland, or will be even more happy in full sun. The large tap-root helps it to flower right through the summer, even during periods of drought.

Although the plant can set viable seed, regeneration also occurs through its creeping lateral runners, arising at various points on the rootstock.

Parts used Leaves, flowers.

Harvest In summer (Flowers only for an infused oil).

Key constituents Hypericin; pseudohypericin; flavonoids (including hyperforin, kaempferol, luteolin, quercetin, rutin); phenolic acids (including caffeic acid, ferulic acid, chlorogenic acid); xanthones; mono-amine-oxidase-inhibitors (MAOIs).

Actions Anti-depressant, anti-viral, anti-bacterial, anti-inflammatory, mild astringent.

Pharmacology and uses The chemical composition of St. John’s wort has been well studied, especially in the last thirty years. Documented pharmacological activities include anti-depressant, anti-viral, and anti-bacterial effects. These provide supporting evidence for several of the traditional uses stated for St John’s wort.

In terms of the recent history of British herbal healthcare, St Johns wort has had a somewhat meteoric rise to prominence. Many of its pharmacological activities remain unclear, although a number of actions have reportedly been attributable to hypericin and the flavonoid constituents.

Evidence from a number of randomised controlled trials during the 1990s, highlighted and confirmed the efficacy of St John’s wort extracts over placebo’s, in the treatment of mild-to-moderately severe depression.

St. Johns wort and extracts of it have been shown to be effective against short-to-medium term mild depression, but not long-term or severe depression. As with a lot of plant medicines, there is a need to further assess the efficacy of St. Johns wort, compared with that of standard anti-depressants.

Although the anti-depressant actions of this plant were only elucidated during the last 40 years or so, this plant had an acknowledged ability throughout history to relieve melancholy, as was noted by Gerard in his Herbal (published 1597). Folk medicine records also show many lay-people knew of its power to cure nervousness and low spirits, so it was also used it as a general tonic.

St John’s wort and mono amine oxidase inhibitors

St Johns wort contains molecules known as MAOI (mono-amine oxidase inhibitors). As their name suggests, the MAOI action is an inhibiting one. These molecules are known to increase the availability of mono-amine neuro-transmitters such as serotonin in the brain (thereby helping to combat feelings of depression). This plant is known to increase deep sleep and can be useful in cases of insomnia. 

Hypericin – a weak MAOI, but exerting effect on other neurotransmitter sites.

Interestingly though, the MAOI in this plant are weak and have been shown not to be responsible for the anti-depressant effect of St. Johns wort! However, what scientists do know about hypericin and the flavonoids are that they exert a number of effects on both the GABA (Gamma Amino Butyric Acid) and Glutamate receptor sites in the brain. These neurotransmitters are directly involved are in feelings of well being and in helping our central nervous system relax.

A number of concerns have been raised by allopathic practitioners over possible dangerous interactions between St John’s wort and certain prescribed medicines (including warfarin, ciclosporin, theophylline, digoxin, HIV protease inhibitors, anti-convulsants, selective serotonin re-uptake inhibitors (SSRI’s), ‘triptans’ and oral contraceptives).

Medical advice in Britain and America usually states that patients taking the aforementioned medicines should not take, or stop taking St John’s wort! Before embarking on a course of St Johns wort, and especially when on other medication, you need to seek advice from a pharmacist or another healthcare professional with detailed knowledge about these potentially dangerous adverse interactions!

Concentrating on the anti-depressant substances in St Johns wort could detract somewhat from the many other traditional applications for which this plant has been used.

Interestingly, a book by Gabrielle Hatfield and David E Allen, titled ‘Medicinal Plants in Folk Tradition – An Ethnobotany of Britain and Ireland’, which was published almost 10 years ago, suggests that the reputation St. Johns wort has for healing cuts, grazes, and more serious wounds and burns, is likely to be more attributable to all of the Hypericum species found in Britain, rather than the one species under discussion in this monograph.

A different Hypericum species on a limestone cliff in the Gower, south Wales

Moreover, St John’s wort is a name given to more than one Hypericum species, and judging by maps of the British flora, H.perforatum won’t be found in all the areas that records of ‘St Johns wort’ use has been documented.

In their fascinating book, pieced together using information from before mass public travel and transportation, and sourced notably from unconnected areas of the UK and the Isle of Man, the authors report that various Hypericum species have been used, and seemingly with much effect.

St Johns wort oil has long been known of, for its topical pain relieving and soothing action on burns and scalds, ulcers, inflammations, and various forms of muscular pain.

Tutsan – Hypericum androsaemum. Likely to have been used medicinally in lieu of St Johns wort.

The red-coloured infused oil, extractable from the petals, has been used for these and other related complaints. St Johns wort can be usefully employed to treat conditions such as neuralgia, fibrositis, sciatica, excitability, anxiety, and as a general nerve tonic.

St Johns wort also aids the regeneration of granular tissue during healing of wounds. Indeed, Nicolas Culpeper, described in the 1640’s that it was “a singular wound herb” and that “it closes up the lips of wounds”.

Today, St Johns wort is a well known species and one of our most widely used herbal remedies. Contemporary uses have built on the fragments of traditional folklore collated from these islands. It is one of the staples of any Materia Medica here in Britain, and due to it being so common, one you can easily harvest, process and store each summer.

Foraging Coltsfoot

Foraging coltsfoot – An ancient and potent herbal medicine for the lungs

Tussilago farfara – Coltsfoot. Asteraceae family

We have been foraging coltsfoot for medicine for thousands of years, and its importance to our materia medica remains.

We know from Roman times that this herb was one of our ‘go-to’ remedies for respiratory disorders. Such was its prominence, if you were to walk into an apothecary in the 17th and 18th Century, you would recognise this flower immediately from the picture on the signage outside.

Coltsfoot is a small, creeping perennial herb, notable for its habit of producing beautiful yellow  dandelion-esque flowers in late winter and early spring, before its leaves appear.

We now know that coltsfoot flowers open before their leaves, giving rise to the old latin name Filus ante patrum, or, the son before the father. previously people foraging coltsfoot flowers thought they were harvesting a different plant to the leaves, because of the unusual floral display
The ‘son before the father’ was how coltsfoot was formerly described, due to its flowers opening before the leaves

As a result of this floral phenomenon, the ancient Latin name given to it by botanists of the renaissance period (before Linnaeus and his binomial classification), was Filius ante patrem, which means ‘the son before the father’. The ancient apothecary physicians used this flower as the emblem for their shops, and it is still used by many herbalists today. 

This plant is one of 15 different species in the genus. Many scientific plant names contain clues as to a plant’s origins, or its favourite habitat, and sometimes to a plants main actions or uses. With coltsfoot, the generic name Tussilago offers the hint towards its medicinal use.

It has been a popular anti-tussive (cough reflex inhibitor) herb for centuries and recent research is backing up some of the ancient claims. The specific name farfara, is apparently derived from the ancient name for the white poplar tree (farfarus) whose leaf colour and form resembles coltsfoot somewhat. Our ancestors obviously thought it looked like the foot of an animal, hence the name coltsfoot.

What to look for when foraging coltsfoot.

This is a hardy plant, native to Europe, West Asia, and North Africa. It re-emerges each year from a rootstock of stout, scaly, white (ish) rhizomes. These give rise firstly to its yellow flowers, before the long-stalked, somewhat hoof-shaped, sea-green leaves appear.

The leaves will typically grow somewhere between 10-25 cm long. They have a few, small angular teeth on somewhat undulating margins.

People who regularly go foraging coltsfoot, know that it can be found on the poorest soils.
Coltsfoot is happy finding a home on the poorest soils

The leaf surfaces when young are  covered with loose, white, woolly hairs, but those on the upper surface will fall off as the leaf quickly grows and expands. The broad leaves have angled, sometimes pink-tinged, main veins, running away from the central vein, akin to the burdock to which coltsfoot is not too distantly related.

Coltsfoot’s composite flowers are pretty similar in appearance to the dandelion at first glance, although the flower stems are quickly seen to be different. Coltsfoot’s terminal flowering stems are scaly and slightly woolly (unlike the dandelion), topped with striking yellow flower heads. More information on how to identify the daisy family can be found in my plant family patterns article.

These striking blooms consist of yellow disc florets and yellow linear ray florets (unlike dandelion which has ray florets only). The flowers will generally grow to no more than 20-25 cm high, and always appear before the leaves have emerged. 

As with many of the daisy family plants, coltsfoot produces a spherical seed head of tiny fruits (achenes), attached to downy white, silky, pappus hairs. Goldfinches were known to line their nests with these soft hairs, as were the Highland peoples of Scotland, who reportedly suffed mattresses and pillows with them.

This plant used to grow far more abundantly throughout England. Yet it can still easily be found on a range of sites up to altitudes of 950 metres. These include waste-grounds, along the sides of railway banks, on cliffs and dunes, and occasionally on roadsides. It grows as well in wet ground as in dry situations.

Nowadays however, with the ever increasing development in 21st century Britain, its abundance has been curtailed somewhat, especially in urban areas. However, when foraging coltsfoot, you will find it still thrives in towns, in any place that remains a little wild, rough, and unkempt.

Young coltsfoot leaves, already displaying the angled margins without serrations

Be sure it is not the young leaves of Butterbur (Petasites officinalis, syn P.vulgaris syn P.hybridus), or the winter heliotrope (Petasites fragrans) you are collecting by mistake when you are foraging coltsfoot! To help your identification, I have covered winter heliotrope in my foraging videos.

Make sure you know the difference in the foliage between Petasites species and Tussilago when you are foraging coltsfoot
Winter heliotrope has larger leaves, without the angled margins or downy white covering

Both of the Petasites  resemble coltsfoot in flowering habit and leaf shape, although butterbur is less likely to be mistaken when mature, because its leaves are so much larger than coltsfoot’s. 

Both of the Petasites species have more rounded leaves, and without the slightly angled and toothed margins or the white downy fuzz. Butterbur can frequently be found dominating areas of canal and river banks.

Winter heliotrope will similarly be found in large carpeting expanses, be this at the edges of woodlands or hedgebanks, as well as other shady spots.

Coltsfoot loves life by the sea. On the Jurassic coast in Dorset for example, and repeated on much of our coastline, this plant grows in reasonably large populations. When I was there in 2011, it was clearly enjoying the North West coast of England close to the Lake District, enjoying the long stretches of sandy dunes and eroding field / beach edges to be found there.

Coltsfoot has been classed as an invasive plant not suitable to garden cultivation by the RHS, but to be fair, this organisation is not widely known for either their medicinal herb gardens, or specialisation in wild medicinal plants, or come to think of it, organic gardening principles.

You, like me, may think that invasiveness and rapid colonising of bare soil is a valuable asset in the medicinal herb gardener’s fight against weeds. If I had a medium-large medicine garden, then this plant, along with other effective ground-covering medicinal species, such as ground ivy (Glechoma hederaceae), would be a most welcome and valued addition to the medicine cabinet.

Parts used Leaves and flowers (the flowers were formerly much used, but not so today as you will shortly discover).

Harvest Leaves: when fully-grown. Flowers just before opening.

Key constituents Flowers: mucilage; flavonoids (rutin, carotene); taraxanathin; pyrrolizidine alkaloids (senkirkine, senecionine, tussilagine). Leaves: mucilage; flavonols (quercetin, kaempferol and their glycosides); tannins; inulin; phytosterols (sitosterol, stigmasterol, taraxasterol); sesquiterpene (tussilagone); zinc.

Actions Expectorant, anti-tussive, demulcent, anti-catarrhal, anti-inflammatory.

Pharmacology and uses Coltsfoot was formerly a prized pulmonary tonic and curative against emphysema, chronic bronchitis and whooping cough. There are still many reasons to go foraging coltsfoot.

Culpepper mentions that  “…the fresh leaves, or juice, or syrup thereof, is good for a bad, dry cough, or wheezing and shortness of breath”.

With the emerging flower buds and yellow flowers, foragers will know that its almost time to start foraging coltsfoot
The buds and first flowers signify that its soon time to start foraging coltsfoot.

The substantial amount of mucilage in coltsfoot confers the demulcent and expectorant activities.

This is also true of other soft leaved plants, such as mallows (Malva spp) and mullein (Verbascum thapsus), and is something worth remembering when out and about foraging…namely, that soft-to-the-touch leaves, usually mean a soft and demulcent medicinal action when taken internally.

Previously, this meant that many people smoked the flowers to help with coughs. The ancients of Greece and Rome were known to advises this, including Dioscorides, Galen and Pliny. We now know that this method is not the best way forward, although you can still find coltsfoot in a number of herbal ‘tobacco’ blends.

Just like its relative elecampagne (Inula helenium), the roots and flowers of coltsfoot have been used to make a cough sweet. Boiled in honey or sugar syrup, a type of ‘rock’ made with coltsfoot was once a popular remedy to alleviate coughs and asthma, which was especially useful to people who almost unfailingly were to sit in dusty churches for a few hours, at least once a week.

The overall anti-inflammatory action of coltsfoot is reportedly similar to the pharmaceutical drug indometacin. The water-soluble polysaccharides are partly responsible for the anti-inflammatory action, as they are in a number of other species in the daisy family. The trace element zinc, reportedly found in reasonabaly high amounts in coltsfoot, also adds to the anti inflammatory action. 

The alkaloid tussilagine has been demonstrated as an effective cardiovascular and respiratory stimulant. However, as with a number of plants containing the pyrrolizidine alkaloids, liver toxicity from chronic low exposure has been demonstrated in tests, albeit mainly on rats.

Further to this, pregnant women are known to pass on toxic pyrrolizidine compounds to their unborn child, resulting in at least one reported case of fatal, hepatic veno-occlusive disease. This death was of a newborn infant whose mother had regularly taken cups of herbal tea containing coltsfoot and a Senecio species (a genus also known to contain pyrrolizidine alkaloids).

It is now believed the budding flowers of coltsfoot contain the highest concentrations of these compounds, so current advice from pharmacologists is usually that only the leaves should now be used in a tea, and not for prolonged use.

Coltsfoot has been shown to be anti-bacterial against bacteria including Staphylococcus aureus, Proteus spp and Psuedomonas aeruginosa.

It is also a mild diuretic and has been used to treat cystitis. There are no documented adverse drug reactions recorded for coltsfoot.

Coltsfoot leaves have also been used as a vegetable. The downy leaves can be simmered and blended with onion and potato into a thick soup, or the leaves can be steamed like spinach, then served with a knob of butter. Some authors have said the leaves have a liquorice flavour. I do detect a sweetness in coltsfoot leaves, but liquorice is pushing the description somewhat. Well, to my smokers palate at least.

Want to know more about foraging coltsfoot? Try the classic Mrs Grieves online herbal.

Discover lots more plants that can easily be found in winter and spring in my short seasonal guides. Alternatively, you can peruse my monthly wild food guides, that began this January, in conjunction with these colour coded seasonal harvest charts, that are available as a download, so you never a foraging trick this year.

If you are wanting more help in the field with learning the arts and crafts of foraging, then check out these pocket sized, waterproof I/D cards, created in a field guide style, then pop over to my foraging courses page and find a course near you.

Toxic and poisonous plants.

Toxic and poisonous plants: To learn them is to leave them!

When starting out on your foraging adventures, plant identification books should always, always be used so that you can get to know the toxic and poisonous plants. Safety is paramount. If in doubt, leave it out!

The British Medical Association define a poison as “a substance that, in relatively small amounts, disrupts the structure and/or function of cells”. You can read more about the various substances and classes of molecules in this summary of medicinal plant constituents.

The subject of toxicity is an interesting yet by no means simple one. Simplicity would demand an answer to the question…What constitutes a poison? A famous name in medieval alchemical science – Phillip Theophrastus Bombastus von Hohenheim, better known as ‘Paracelsus’ (1493-1541), recognised that…“it depends only on the dose whether a poison is a poison or not”!

Certain drugs, notably many anti-cancer agents (whether natural products or synthetics), are principally used because of their toxicity.

A number of our cultivated plants that we can safely consume in normal dietary amounts are potentially toxic, if consumed in larger quantities. We all know of at least some of the health benefits from eating regular amounts of cabbage or broccoli. However, the knowledge that excessive consumption of cabbages, kale and cauliflowers (all are cultivated varieties bred from the wild cabbage, Brassica oleraceae) can lead to swollen thyroid glands is not so widespread.

There are documented cases of rural communities reliant on brassica’s as staple foods, inducing thyroid-related illnesses from over-eating cabbage and cabbage relatives. The medicinally valuable glucosilinates are widespread in members of the brassica’s, and are toxic in large amounts. However, it is physically impossible to eat enough in one sitting.

Within the fruits of many rose family members are minute amounts of arsenic-based cyanogenic glycosides (in the form of prussic acid – hydrogen cyanide). Arsenic is known to be deadly poisonous. However, the concentrations are usually so low that they have beneficial medicinal effects.

Different plant parts will hold various concentrations of poisonous compounds. Typically the fruits, seeds and roots will contain considerably higher amounts of toxins than the leaves and stems. Some plants will also let you know by their smell that they are inedible. For example, the scent of elder leaves are unpleasant and do not invite eating.

Plant families can be usefully, if roughly, categorised as to their general edibility, medicinal value, and toxicity. Some families are edible and medicinal, others medicinal and toxic, whilst some are downright toxic.

Commonly found plant families; their toxic and poisonous plants.

The dock family.

Although these are edible, there is a need to point out the risks of eating plants with oxalic acid (see medicinal chemistry), the major constituent of sorrel (Rumex acetosa). Oxalic acid is a ubiquitous plant constituent. High oxalate consumption can lead to kidney stones or gout. As a foraged or cultivated vegetable consumed every now and again however, this plant, or indeed the family as a whole, presents little danger.

Oxalic acid is also present in Rhubarb (Rheum spp), as they are in many other plants in this family, along with numerous other unrelated plants. Be sure to wash the leaves of the dock family because they can have chrysophanic acid on the surface which can make the tongue numb. This property apparently gave them the common name of ‘smartweed’ in North America, as when eaten raw they could make the tongue smart!

The lily family.

Many bulbous plants in this family are edible and medicinal (Allium spp), yet bluebells (Endyion non-scriptus syn Hyacinthoides non scriptus) and true hyacinths (Muscari spp), contain toxic substances. The very beautiful, but poisonous autumn crocus (Colchicum autumnale), is found in damp meadows and woodland, especially in a belt of central England from North Dorset up to Shropshire and across to Oxfordshire.

Closely related plants in the Narcissus genus (Amaryllidaceae family) are also toxic, though a substance found in daffodils is known to help with types of dementia. The gorgeous, spring-flowering ‘snakeshead’ fritillary (Fritillaria meleagris), is poisonous due to its alkaloids. These plants are usually quite rare in the wild now, and vary easy to identify with their striking snakeskin pattern, so present no real danger of mistaken picking in reality. During flowering it should be unlikely to be mistaken for edible or medicinal species. Fritillaries do not offer us food or medicine but are a treat for the eyes when stumbling upon them.

The pea family.

These plants, or more specifically the seeds, are often inedible when mature and raw. The ornamental laburnum tree (Laburnum anagyroides) has extremely poisonous seeds. Many of the whole-foods commonly we commonly eat are seeds of this family. These include the soya bean (Glycine max) and kidney beans (Phaseolus spp) amongst others. These plants contain substances such as trypsin inhibitors and certain enzyme inhibiting substances which will otherwise interfere with our digestion and metabolism. Our common wild legumes, including the Vicia (vetches) and Lathyrus (sweet pea) genera, are known to contain trypsin inhibitors.

The nightshade family.

Aside from mostly being very pretty to look at, this family supplies us with a range of different foods, medicines, hallucinogens, and outright nerve toxins. A common nightshade family toxin is the substance solanine. This is a central nervous system toxin and causes dizziness, nausea, diarrhoea, and potentially delirium, shortness of breath, and coma. The well known vegetable aubergine (Solanum melongena), is toxic unless cooked. All parts of the potato (Solanum tuberosum) except for the tubers (unless green) contain solanine.

When foraging, we need to become familiar with the following poisonous plants:

Bittersweet (Solanum dulcamara); populates lanes and hedges throughout Britain. It has a twining, sprawling habit, decorated by its 8-10 cm oval leaves which often have two smaller pointed leaves at the base. From June to September the purple and yellow-coloured flowers are scattered in amongst the green leaves of the hedge and are followed by increasingly noticeable scarlet berries in the autumn. These shiny red berries look enticing, but are to be left for the birds!

The ‘deadly nightshade’ (Atropa belladonna) can be fatal if consumed, yet is reasonably rare outside of the South East of England. It can be identified by its pointed, 20 cm long oval leaves, and its distinctive flower and fruit. The flowers are produced singularly, or in pairs, and are bell-shaped with more or less parallel sides and blunt lobes. The corolla is striped with a brown-purple or green hue and is succeeded by the solitary, shiny black berry. The fruit sits with the five pointed calyx noticeably persisting behind it. This calyx/berry arrangement is happily unlike any edible berry and should not easily be misidentified for one.

The black nightshade (Solanum nigrum), is a common weed of agricultural fields and gardens alike and probably our most common nightshade. The green berries are poisonous, containing solanine, although the ripe black berries are edible.

The leaves of balck nightshade also contain variable amounts of solanine but this is destroyed by boiling so they can make an acceptable wild green. The leaves also contain the amino acid methionine, which is rarely found in plants.

Both henbane (Hyoscyamus niger) and the thorn apple (Datura stramonium) are used in herbal medicine practice, and both are controlled under schedule 3 due to their toxicity. These plants are therefore not advised to be used by unqualified people. Henbane has no resemblance to any edible species found wild in Britain, so is not of any realistic concern to the forager.

Datura on the other hand, although pretty uncommon, could be mistaken for one of the not uncommon beetroot family – the ‘maple goosefoot’ (Chenopodium hybridum). With a similar shape and outline to their leaves, confusion is not impossible even though the foliage of the goosefoot does not smell like Datura. It is safest to avoid picking the maple goosefoot altogether, just in case.

The buttercup family.

The vast majority of this family are quite unpalatable and poisonous to us. Have a nibble of a buttercup leaf and spit it out. They taste acrid, bitter and nasty and do not invite eating! Indeed, one of the most powerful toxins known to man is in this family. The monkshood, also known as wolfbane (Aconitum napellus), has a long historical use as a poison, especially as an arrow poison. It contains the deadly poison aconitine, present in large concentrations in the roots.

A very common climbing-vine known as ‘travellers joy’ or ‘old man’s beard’ (Clematis vitalba), is rare for a buttercup in that it has only four petals not five. This plant has also been documented as poisonous although the young tips are edible with cooking, as this breaks down the irritant compund protoanenomin, common to many buttercup family plants, such as lesser celandine (Ficaria verna). The other common name of this latter plant, ‘pilewort’, will tell you its primary medicinal use!

The carrot family.

The following are all documented as poisonous by the Royal Botanic Gardens at Kew.

  • Aethusa cynapium fools parsley –Found in most areas of Britain. Commonly a garden weed. Large prominent bracts.

  • Berula erectawater parsnip – Common by waterways. Tastes of parsnip!

  • Chaerophyllum temulum syn Chaerophyllum temulentum – rough chervil – Common.

  • Cicuta virosa cowbane – Very rare, except North-West Wales, Cheshire and South Lancashire areas. Absent South-West. Very poisonous!

  • Conium maculatum poison hemlock – Deadly poisonous and widespread over Britain.

  • Ferula communis giant fennel – Extremely rare introduction.

  • Oenanthe crocata water hemlock dropwort – Deadly poisonous and very common by water.

  • Oenanthe fluviatilisriver water dropwort – Locally common in South and East Britain. Not widespread.

  • Oenanthe fistulosa tubular water dropwort – Locally common in certain areas prone to winter flooding.

  • Oenanthe pimpinelloides corky fruited water dropwort – Uncommon but found in Somerset, Dorset, South Gloucestershire, and Hampshire.

  • Oenanthe silaifolia narrow-leaved water dropwort – Absent Scotland and Wales. Rare in England, absent in South West.

  • Oeananthe aquatica fine leaved water dropwort – Found sporadically from the Severn right along the welsh borders to the Mersey and some parts of East England.

  • Oenanthe lachenalli parsley water dropwort – Found around the coast, rarer inland.

  • Sium latifoliumgreater water-parsnip – Common by waterways.

  • Sium suave – Also (confusingly) commonly known as water parsnip! – Rare.

A number of these poisonous plants contain powerful nerve toxins. Poison hemlock and water dropwort hemlock are both deadly poisonous. They look distinct to each other, yet for the beginner they can appear very similar to a number of other edible umbellifers. This then is one of the overarching issues when foraging for umbellifers. The edible ones look incredibly similar to some of the poisonous ones. Saying this, each of the umbellifer species are said to be distinct to each other, and are not known to hybridize that frequently.

Extreme care and caution should always be exercised when foraging for the carrot family. Avoid foraging for umbellifers next to waterways until you know them really well, for this is where a number of the poisonous ones live. Let’s face it, no one wants to look silly by dying in a hedge after mistaking hemlock for one of the numerous other similar looking umbellifers!

Hemlock contains the extremely poisonous alkaloid, and nerve toxin, coniine. As a very inexperienced, naïve and reckless forager many years ago, I discovered this plant in my mouth seconds after misidentifying it from a peripheral glance as wild chervil, whilst strolling and nibbling on a mixed hedgerow salad (please, don’t ever be this stupid). Its bitterness rapidly turned into unpleasant sensations akin to stinging needles erupting throughout my mouth and I quickly spat it out. Thankfully, I had pinched off only the top inch or so and had yet to swallow, so got away with a short, sharp, shock!

The plants below are all documented as recording a range of photo-sensitive, dermatological effects. These are due to furanocoumarin molecules. If sap from the stems (produced in profusion when flowering) of these plants comes into contact with your skin under the sunlight, then mild blistering may occur, and in the case of giant hogweed, 3rd degree burns. As you will see, some of our common vegetables are included. I know a farmer who has suffered mild burns from cutting down flowering parsnips in the summer sunshine.

  • Apium graveolenscelery

  • Angelica sylvestris wild angelica

  • Anthriscus sylvestris – wild chervil / cow parsley

  • Daucus carota – wild carrot

  • Foeniculum vulgare – wild fennel

  • Heracleum mantegazzianumgiant hogweed

  • Heracleum sphondyliumhogweed

  • Pastanaca sativa wild parsnip

  • Petroselinum crispum parsley

  • Thapsia garganica drias plant


It needs to be stressed here that the giant hogweed is, by far, the plant most commonly documented as responsible for the most severe reactions. The others produce much milder effects, which not everyone experiences to the same degree, if at all.

The concentrations of furanocoumarins present, degree of sunlight, and an individual’s constitution will all play a part in reactions experienced following exposure to the sap under sunlight. I happily eat raw, peeled, wild chervil stems in the spring sunshine and do not have any problems from handling the plants.

For safety, I do not touch giant hogweed at all. The ‘drias plant’ I have not yet met. Wearing gloves and harvesting on overcast days or out of direct sunlight is the answer if you are in any doubt. A number of plant families including the spurge (Euphorbiaceae) and citrus (Rutaceae) families also exhibit similar photo-toxic effects.

Other widespread poisonous plants of Britain.

Our native evergreen climber, the common ivy (Hedera helix) produces poisonous berries from November, initially green then turning black through the winter that are best left to the birds. They contain the toxic substance hederin. It was formerly used as a purgative medicine, but one considered too strong for safe self-medicating.

The dogwood (Cornus sanguinea) is a common ornamental and hedgerow plant of the Cornaceae family. Its white spring flowers give rise to black berries in the autumn. They may seem appealing, but leave them alone! Holly, the well known evergreen tree, contains the toxin ilicin in the berries. As little as two of these may induce nausea.

The same advice goes for two previously used strong purgatives, the buckthorn (Rhamnus catharticus), and the alder buckthorn (Frangula alnus). Both shrubs carry black berries in the autumn following flowering. Buckthorn’s broadly elliptical leaves are noticeable for their curving vein patterns. Their small and green flowers have four petals and are borne in clusters at the base of the upper leaves.

Alder buckthorn is thorn-less and also displays small flower clusters. The small white flowers contain five petals, and give rise to a black berry which is red until ripe. Both plants are found occasionally in hedgerows in Britain (although rarer in Scotland).

Look-a-like poisonous and toxic plants

The perils of similar looking yet unrelated species needs a mention at this point. The common ‘lords and ladies’ (Arum maculatum), has often been mistaken for two popularly foraged plants; sorrel and wild garlic (Allium ursinum). I heard from a forager friend that should you try and eat the leaf from the lords and ladies, a sensation akin to the one I described for hemlock will ensue. The leaves contain toxic calcium oxalate crystals. Note that this compound is different to oxalic acid, present in the sorrel and prevalent in other members of the dock family.

Both the common sorrel and lords and ladies have a relatively similar shape to their leaves, especially when small, although their leaf vein patterns are unlike. The favourite habitats are also completely different. Sorrel loves meadows, fields and other grassy areas, whilst lords and ladies is a natural woodland species and hardly ever extends from the protection given by woodlands, roadside verges, hedges, and darker edges of fields.

Beginners reading this may already be aware of the similarity between very young wild garlic leaves and any emerging lords and ladies leaves. The two plants often share woodland and other habitats.  Arum does not have parallel veins like wild garlic, and its prominent basal lobes are distinctive, as are the arrow-shape leaves. Compare these to the broadly-elliptical leaves of wild garlic. IMG_4449

This picture demonstrates that edible and potentially deadly poisonou plants will often be found side by side.

Notwithstanding the fact that wild garlic tends to emerge after the lords and ladies is already up, and that the two plants soon display noticeable differences in leaf shape, care should always be taken when you are first foraging. If the leaves are too small to be sure of positive identification, move on. This advice goes for any plant!

Sorrel has a lo-k a-like with a similar habitat, the meadow resident, field bindweed (Convolvulus arvensis). This has similarly-shaped leaves to sorrel, and enjoys sharing some habitats, but it’s striking, raspberry ripple, two-toned flowers and creeping sprawling habit, are completely different to sorrel.

A common poisonous member of our woodlands is the perennial herb, ‘dogs mercury’ (Mercurialis perennis). This poisonous plant can carpet some woodlands and hedge-banks. Dogs mercury can slightly resemble a nettle when in flower for it also has white, thin and wiry clusters of flowers appearing from its upper leaf axils. The rare, but pretty yellow-flowered birthwort (Aristolochia clematis) contains the highly toxic compound aristolochic acid, which causes renal failure.

Our only native member of the Curcubitaceae family – Bryonia dioica, or ‘white bryony’, is also documented as a poisonous plant. Its palmate leaves could be mistaken for hops. Both the plants share similar habitats. The classic pumpkin family characteristic shown in bryony’s spiralling, wrap-around, spring-like tendrils help the plant get into the light. The dainty white flowers can be seen dotted in the hedgerows during the summer months if looking closely. The roots and berries are toxic. An alkaloid, bryonicine, is partly responsible. The young downy shoots stretching up from the soil could be mistaken for hogweed reaching for the light. Red berries follow the flowers.

The unrelated ‘black bryony’ (Tamus communis) is the only species in the yam family to grow wild here. Another of our hedgerow climbers, this plant is notable for its dark glossy-green, heart-shaped leaves and scarlet berries. This yam family (Diosceraea) species has been documented as a poisonous plant in some books but edible in others. I have eaten the young tips, which similar to travellers joy, will need cooking to render the toxins present, harmless. The berries are certainly poisonous, but the root reportedly could be eaten if you are prepared to treat it in all number of ways first through boiling and such like. Hmmm, not for me.

I hope you are not now thinking that the land is awash with harmful plants. The reality on the ground is that only four of our poisonous plants here in Britain are likely to be confused with similar looking edible or medicinal species. These are poison hemlock, water hemlock, foxglove and the yew tree. Foxglove is dealt with elsewhere in these pages. The yew tree does not offer the typical coniferous aroma from its foliage and has bright red aril fruits (usually called berries for non botanists) in late summer/autumn. Its fleshy and edible fruits distinguish it from many similar evergreens, as does its growth form, which is more typical of a deciduous tree than a coniferous tree. Remember that all other parts of the Yew could kill you, including the seed, so spit it out if eating the berries.

If you are wanting to learn more about foraging and plant identification, then take a look at my seasonal sets of waterproof I/D cards. These handy pocket sized cards are designed to help your learning in the field.

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