A fly agaric mushroom in a woodland setting

Stinging plants, poisonous fungi and other natural hazards in Outdoor Learning sites

In this blog, we’ll look at some of the illnesses and injuries that can be caused by contact with or ingestion of plants and fungi in the UK.

Nettles (Urtica dioica)

Stinging nettles are easily identified and one of the most common sources of irritation in the outdoors.
The sting comes from the hairs on the stem and leaves and is a great defence mechanism for the plant!

Dock leaves are thought to help relieve nettle stings but there is no proof it works – it may just be a (useful) placebo effect!

Nettles are incredible things! For millennia they have been used as a food stuff, medicinal plant, raw material for natural string and textiles plus dye for fabrics to name but a few. However, most of us know them for their excellent defensive properties, millions of tiny hollow stinging hairs on the stem and underside of the leaves. These contain a variety of unpleasant compounds that can leave us itchy, swollen and generally miserable for the rest of the day!

Though nettle stings are unpleasant they are an easily recognisable plant so a great first introduction to plant ID. As with most things in first aid avoidance is better than cure and knowing what nettles look like and where there are patches is a good way to avoid getting stung. Nettle stings are rarely a real concern and complications particularly from small exposures are extremely rare. To treat a nettle sting many of us instinctively go for dock leaves. Sadly, the evidence to support this is scant at best, though at the very least it may act as a reasonable placebo.

The best course of action for a nettle sting is to give it a good wash with soapy water. This will remove any left-over stinging hairs. Some reports also suggest that the alkali pH of soap has some beneficial effect. Following this we would recommend a cool compress or ice pack if you have one, this will slow the swelling and help to reduce the pain and discomfort. It can also be helpful to reduce the chance of clothing rubbing on the sting. Outdoor clothing especially with sturdy fabrics and numerous Velcro parches and zippers can rub and further irritate the site. We can reduce this irritation by removing heavy clothing or covering the site with a loose section of soft fabric like a t-shirt or triangular bandage.

Though more severe reactions are extremely rare in some cases, with extreme exposure people have reported wooziness, muscle weakness and a variety of other symptoms. If any of these symptoms appear, seek medical assistance.  

Poisonous berries

The berries of the Yew tree are very poisonous to humans, cattle and other mammals.
Deadly Nightshade or Belladonna is a woodland and scrubland plant that is related to
the humble potato but is very poisonous.

There are only a small number of poisonous berries in the UK but ingesting any of them can have serious consequences. First, we need to supervise groups appropriately and enforce a “nothing in the mouth” rule. Probably the most dangerous berries we may come across are Yew (Taxus baccata) and Deadly Nightshade (Atropa belladonna).  Both have small rather tasty looking berries that can be fatal if ingested. In both cases ingesting most parts of the plant can be deadly however poisoning tends to be associated with berries and seeds. In both cases the plants contain a cocktail of compounds that can quickly enter the body and cause a range of symptoms including nausea, dizziness, confusion, sight problems, paralysis and in some cases cardiac arrest.

If anyone you work with ingests an unknown berry or plant take a cutting of the plant, containing if possible, stalk, leaves, and any flowers or berries, this should go with them to hospital to help identify what they may have eaten. On the way to hospital monitor symptoms and vital signs closely and make a note of any changes you see. Never encourage the casualty to vomit or to eat or drink anything to “neutralise” the toxins.

As with much of our landscape a little knowledge can be very helpful. Being able to identify common species is important, and if you don’t know what it is don’t eat it! If you are interested in learning more about the plants on your site, there are a variety of courses available. Every year several people in the UK are poisoned and a death occurs every couple of years due to foraging misidentifications so if you are looking to start foraging either yourself or with your group make sure you get expert advice first. Especially on some of the “confusion species” that can be dangerous and look similar to some of the tasty treats that are out there.

Fungi, mushrooms and toadstools

Many fungi are very attractive but their colouring is often a warning that they are poisonous. This is the Fly Agaric.
Bracket fungi grow on many different substrates and display a great variety of colour bandings. Very few are edible.

The Ink Cap mushroom is edible but only when freshly emerged. Many mushrooms become unpleasant or poisonous as they age.

There are over three thousand ‘macro-fungi’ in the UK – those are the ones that can be seen by the naked eye. They include the mushrooms and toadstools that appear in woodlands and other habitats throughout autumn but they also come in a great variety of other forms. Of these three thousand there are a couple of hundred that are edible and somewhere between fifty and a hundred others that are poisonous. The others can be classed somewhere in the “not too bad for you but don’t try them in a risotto” category.

How poisonous are wild mushrooms?

As you can probably already guess, finding your way through this plethora of species to the good ones takes a lot of experience and training so should only be done under expert guidance. There’s not much room for ‘trial and error!’  However, fungi are everywhere and are great to study. To the fungi, the little toadstools you see are like the apple on a tree – , they are the fruiting body, a mechanism created to help the organism reproduce and spread. The real ‘body’ of the fungi is in the substrate. If you can think of a substrate such as soil, wood, pine needles, alder cones, even dog faeces – there is probably a fungus that specialises on living there.

On our outdoor learning sites we will often come across fungi and kids find them as interesting as us adults. Fortunately, there are no species of fungi in the UK that are toxic to the touch so once again we follow the “don’t put it in your mouth” rule. However, there are a small number of species whose spores are toxic so good hand washing routines are important. Spores are emitted from underneath the mushroom’s cap and may land on your hand if you pick them up during this time.

How often do people get poisoned by mushrooms?

In general fungi poisoning is not hugely common but it does happen. Records are sketchy but in 2013 the National Poison Information Service recorded 237 incidents where they were contacted after someone ate fungi. In many cases poisoning is caused by someone deliberately eating a fungus that has been misidentified. In other cases, a child had eaten a mushroom and not been seen by the responsible adult.

What are the symptoms of mushroom poisoning?

The symptoms of fungi poisoning can be just as varied as the species themselves. Ingesting poisonous fungi can lead to anything from mild stomach upsets or cramps, vomiting, confusion and dizziness to multiple organ failure.

Anyone who has ingested an unknown fungus and is not feeling well as a result, seek medical help immediately. Do not allow the casualty to eat or drink unless advised to by a medical professional and do not encourage them to vomit.

It’s a good idea to collect a specimen of the fungus, nipping a mushroom off just below ground level gives the best chance of preserving all the structures required to identify it. If they have eaten a full mushroom look in the immediate vicinity for more as many species grow in clumps. (Wash your hands afterwards)

Brambles and other thorns

Bramble thorns are the plant’s defence against hungry birds – and children!

Gorse thorns can be quite long and break off in your skin creating a challenging splinter that needs careful removal.

There are a great variety of prickly shrubs but most of them leave us with little more than scratches that can easily be cleaned and covered with a plaster.  In some cases the thorns may be more brittle and leave a splinter. There are a few plants such as gorse and some bramble species that are more prone to this.

How do you remove a splinter or thorn?

To remove a splinter, make sure the area around it is clean using a wipe or soapy water. A set of fine nosed, clean tweezers can then be used to draw the splinter out, reversing the direction it went in. Don’t dig out splinters or try to use safety pins or similar devices to open up the wound as this is liable to introduce infection and break up the splinter making it harder to remove. Once you have drawn the splinter out apply a bit of pressure behind it so you see a little blood being forced out which will flush out any debris. Finally give the wound another wipe down and cover it to keep it clean.

To remove a splinter, pull it out in the reverse direction. Squeeze out some blood from the wound to flush out any debris then clean it and cover with a plaster.

Can splinters and thorns cause infections?

All scratches and splinters can lead to infection, though some species such as blackthorn seem to cause more infections than others. For this reason, we should monitor the wound for a couple of days. Watch for any reddening, swelling or heat around the wound site as well as any pus in the wound itself. If you notice any of these symptoms consult your Pharmacist or GP. This is particularly important for groups far from help on multi-day trips as an infection once established can be debilitating so proper care and cleaning is essential.

A word about Tetanus

Dirty wounds such as those encountered in the outdoors can also be vectors for the spores that lead to tetanus. This can be a debilitating long-term condition with various severe or even fatal outcomes. Though effective wound cleaning is helpful we always recommend making sure those in your care are aware of the risks and have consulted their GP about the tetanus vaccine. This is equally applicable for those of us who work in the outdoor environment.

Want to learn more?

Many of our trainers at the First Aid Training Co-operative have backgrounds in outdoor learning, adventure trekking, mountain leadership and working with all manner of groups in the outdoors. Our Outdoor First Aid for Forest School and  Outdoor Woodland Learning courses are designed specifically for outdoor education practitioners and delivered by trainers with a strong understanding of the sector. We run a number of publicly available courses or we can arrange a private course for you in your workplace. Contact us for more information and to book what may be the most important and relevant first aid course you’ve ever done!

Find out more information about our specific Forest School and Outdoor Woodland Learning First Aid course.

We also have a range of Digital First Aid Manuals available to download from our website including ones specifically for Outdoor First Aid and Paediatric First Aid.