Tales of a burning bush

Tom Cole is employed by Cairngorms National Park Authority as a Community Ranger. In more normal times this time of year would be his busiest work period, but, as for many of us, business-as-usual has been severely curtailed by the impact of the current COVID-19/Coronavirus pandemic.   

The Cairngorms National Park Authority’s most recent advice on accessing the countryside and staying safe with COVID-19/Coronavirus can be found here. (Anything other than local travel is not advised at present.) 

Hiking in the pinewoods after a prolonged torrential downpour see clusters of fluorescent orange horns amongst the undergrowthThe lurid yellowy-orange growths appear strange and out of place amongst the dark and prickly Juniper bushes.  

Gymnosporangium clavariiforme

I look closer and see more of these peculiar structures on the bushes around. Have I discovered some strange xenomorph biota?! 

This is not some alien biota but its story is equally strange.  This species is a type of fungi or rust. Its common names are tongues of fire, or juniper rust fungus. Its scientific name is Gymnosporangium clavariiforme 

Juniperus communis

The fungus has an unusual twostage life cycle. The first stage begins on juniper (Juniperus communis) where the fungus overwinters. Then on damp days in spring, the fungi fruiting bodies erupt from the juniper. These psychedelic looking structures are called telial horns. Perhaps this explains the biblical story of the burning bush? 

Juniper (Juniperus communis) – Aiteann  

Here in the Highlands juniper has many connections with supernatural and mythology such as the ability to divert witches from dwelling houses Witches had had to count every leaf before they enteredJuniper was often planted around houses in the Highlands and it’s easy to see why the prickly tree was once used as protective barrier, much like barbed wire is used today. It can successfully protect more vulnerable plants like aspen from grazing animals, and so far I’ve seen no witches in the woods nearby.  

Prickly juniper can make an effective barrier for livestock and perhaps even witches

The shrub was used in the traditional activity of saining (or seun in Gaelic)Saining was carried out at Hogmanay to purify the house with the smoke of smouldering juniper, much like sage is sometimes used in other places. It has long been used as an herbal cleanser, general pick me up and even (*rather dubiously) for birth control. Traditional recipes often used juniper berries in rich, gamey dishes. These days are lots of inventive modern recipes that use the berries and look like they are worth trying.  

Despite its diminutive size, juniper can live more than a hundred years, and because the tree grows very slowly its wood is dense and hard. This coniferous tree was used in times past in illicit whiskey distilling, as the wood burns hot with little smoke. This helped whiskedistillers to hide their activities from the law. 

But juniper has been even more useful to gin distillers through the ages. By law, this clear spirit can only be called gin if it has been distilled with juniper berries, which give this ever-popular spirit its distinctive and defining flavourIn days of the British Empire gin was widely drunk as it went well with bitter taste of tonic water, and drinking tonic water was encouraged  as it contained quinine–  the then only effective remedy for malaria. These days gin is enjoying a resurgence as a popular tipple, and many Scottish distilleries are now diversifying to produce gin as well as whisky.  

Although common in some places within the UK like some Highland sites, Juniper is struggling in other areas within UK due to a fungal disease Phytophthora austrocedrae and from overgrazing from deer and other grazers like rabbits. 


Juniper is dioecious, in other words the plant can be either male or female. The male plant produces pollen which fertilises the female plants, and these then go on to produce green berries which take more than two years to develop and ripen into the small purple-black berries that can be picked and used. Birds such as capercaillie love to eat these and consequently they help disperse juniper seeds. 

Hawthorn ​(crataegus monogyna) ​- Sgìtheach  

The second host of the fungi, ‘Tongues of Fire is the hawthorn. Look for structures on the underside of leaves. Hawthorn is sometimes called Quickthorn because of its fast growing speed. That combined with its thorny nature make it ideal for hedging.  Planting a hedge of predominately hawthorn in your garden is a great way to help boost wildlife. 

Juniper berries take two years to ripen

Hawthorn has sharp thorns and is excellent for hedging

Niver cast a cloot till mey be oot.” This traditional saying translates from Scots (Scots is a Germanic language related to Englishas don’t dispense with winter clothing until the hawthorn blossoms (which is usually early May). 

The hawthorn blossom in spring has long been associated with fertility, and the pagan festival of Beltane which celebrates growth and fecundity. Hawthorn coming into bloom signalled the coming of summer.  

It is said that Christs crown was made of hawthorn. In medieval times when plague stalked the land, hawthorn wood (which burns at a high temperature) was burnt on funeral pyres as it was thought to help guide the dead to the afterlife. 

The tree has a wide range of invertebrates which thrives on it. It provides pollen for insects and the thorny tree is an excellent nesting tree for birds. The berries or haws are an important food source for animals and can be used by us to make things like jam and jelly.  The flowers and young buds are edible – but I’ve not acquired a taste for the young leaves yet. The tree also has a wide range of herbal uses such as treatment for sore throats.  

Aspen ​(Populus tremuloides) ​ Critheann 

In the woods near where I often walk there are many Aspen. The tree is late in coming into leaf but can be easily identified by its pale grey bark with a distinctive diamond-shaped pattern. The Latin-scientific name (Populus tremula) translates as ‘trembling poplar.’ In Gaelic the name critheann comes from the word crith which also means tremble.  

Aspen is one of my favourite trees because when a light breeze catches its leaves, they shimmer in an ethereal manner; and in autumn the leaves turn a glorious golden colour.   

Aspen trees have distinctive diamond-shaped bark

In Scotland the constantly shimmering leaves were equated either with gossiping women, (hence why tree was once known as old wife’s tongue), or because the tree was trembling in shame; aspen is associated with the cross that Christ was crucified on. Highland tradition was to scold an aspen tree on Good Friday for its sins. Superstition followed Scottish colonists to Canada and tales have been told of lumberjacks there who were so wary of aspen that they would refuse to stay in a log cabin made of the wood.  

The aspen has a strong connection with the divine in myth and folklore.  In pre-Christian times the wood was said to protect shield bearers with magical protective qualities and it was seen as so lucky that it could help protect householders if planted near their house. It was said to protect heroes entering the underworld. The remains of aspen leaves thought to be from wreaths have been found in 5000-year-old graves in Mesopotamia (modern day Iraq) 

As far as I my research could find out it seems unlikely that aspen (Populus  tremula) ever grew in the Middle east, and was more likely to have been the closely related silver poplar (Populus alba) or Euphrates poplar (Populous euphratica). 

At the end of the ice age, aspen trees were amongst the earliest tree colonisers in the barren landscape left behind by retreating glaciers. Although uncommon now this type of poplar is still found in Scotland, particularly in Strathspey where it is found in scattered pockets. Unfortunately the tree is scarce these days, because it is favoured by large herbivores such as deer which are present in very high densities throughout much of Scotland. Cairngorms Connect and Trees for Life are making a big efforts to propagate the tree to help restore its place in to some areas of Caledonian forest that remain.  

Male and female trees may be in isolated pockets some distance from each other. This is not an insurmountable problem for the aspen as it can spread by suckering. Suckering is a growth from a tree (or shrub) root system that can form a new tree.  This gives it and an advantage in areas disturbed by fire or other large scale disturbances.  

Aspen growing among some downy birch

Latterly, aspen suffered from a superstitiously bad press, due to its aforementioned links with Christ’s crucifixion, and perhaps due to this tarnished reputation the tree was rarely planted in Scotland.  

Naturalists find the tree immensely interesting as it supports a variety of species including the rare aspen hoverfly (Hammerschmidtia ferruginous) and the dark boarded beauty moth (Epione vespertaria)Plus many rarer or nationally important species including flies, moths, beetles, fungi, lichens, and mosses.  

Native trees in Scotland have a rich historic folklore which is well worth investigating, much of this rich heritage is reflected in place names, such as this place name in Deeside; Tom nan Critheann which means Hillock of the Aspen. 

Place names are an interesting and involving subject but I will perhaps save this for another blog post! 

Blog Native Species Virtual
Location: Cairngorms National Park Wide Date: May 22, 2020 Time: 9:00 am - 11:59 pm