This article was originally published in The Bushcraft Journal Issue 19. If you don’t yet subscribe, hurry up!
Outer barks as tinder
So far we’ve looked at downy flower heads and inner barks as tinders. We saw that both of these categories have plus points but that they also have drawbacks – downy flower heads aren’t available all year round and inner barks need to come from trees in a specific condition, standing dead. This time around I want to look at outer barks which have the advantage of being available all year round and can generally be taken from live trees and plants without causing harm.
Probably the outer bark that most people are familiar with is birch bark (Betula). Birch are common throughout the temperate and boreal areas of the northern hemisphere. In the British Isles you’re most likely to encounter silver birch (Betula pendula) or downy birch (Betula pubescens) although there are plenty of imported ornamental species found in gardens and parks. There are 12 – 15 species in North America, of which the only one I’ve tried as a tinder is yellow birch (Betula alleghaniensis) which I collected during a visit to Lake Michigan about 10 years ago.
If you see a birch with its bark peeling away, it’s perfectly fine to remove, you won’t cause the tree any harm.
I currently have 3 ideas as to why birch shed bark: to speed a forest fire through in the same way eucalyptus does, to get rid of pollutants, or because the tree is growing faster than its bark. The fact that, in my experience, birch tend to peel most when they’re young suggests it might be this last idea, but I don’t know for sure. If you know, please let me know!
It’s the second most common tree in the British Isles and grows in a wide variety of habitats and is generally easy to find. This is a good thing because birch is a fantastic resource for fire lighting. The bark is extremely flammable due to the betulin it contains; betulin is a triterpene, think turpentine (a terpene). In fact, it’s this betulin which gives the genus its name.
You can also cut strips of bark from a birch and fluff up the outer side with your knife. This isn’t a technique I’d use on a living tree as it will harm the tree.
When they’re young they can often be purple and look superficially similar to cherry, which leads into….
Like many fruiting trees, cherry is complicated in terms of its cultivation and distribution. Wild cherry (Prunus avium) is native to Europe, western Asia, north Africa and has a small population in the Himalayas. It’s become naturalised in North America and Australia.
Unlike birch, where you can peel bark off without harm, you need to be more cautious with cherry; tug gently and if the bark doesn’t come off easily, stop. If you continue you’re likely to expose the cambium layer and allow infection into the tree.
We have dozens of wild cherry in our ancient woodland in Kent (and sometimes I even manage to get to the cherries before the local wildlife!), but none of them particularly peel, in fact when I‘ve found cherry bark that peels easily it has been on cultivated varieties in parks.
Cherry bark is incredibly robust and often survives long after the wood inside has rotted away. Cherry bark harvested this way can also be used as a tinder.
Hornbeam (Carpinus) can be found throughout the temperate parts of the northern hemisphere; we have 2 species in Europe, there’s one in North America with another 30 or so species spread across Asia.
They’re similar to beech (Fagus sylvatica) in terms of shape, structure, leaves and buds but they’re not related, it’s a case of convergent evolution. For me the bark on a hornbeam looks like a snake’s skin, with silver streaks running along the trunk.
When I introduced natural tinders, I suggested that you should experiment with them. Well, a couple of years back Bob, one of our instructors, brought some hornbeam (Carpinus betulus) bark into camp.
He’d found it on a standing dead branch on a live tree, picked some and taken a lighter to it; it burnt well. So we took a fire steel to it. It glowed but didn’t create a flame so Bob scraped a pile of shavings from his fire steel into the bark and then put a spark to it. It burnt with a good, hot flame and is effective for lighting kindling.
As I said, this was a new one to me, I hadn’t come across hornbeam bark being used as a tinder before, but I do wonder if hornbeam bark also contains betulin, it’s in the same family as birch and the species I tried is called betulus! As to other species of hornbeam, I have no experience of them; if you’ve tried, I’d be glad to hear how you got on.
Making it’s third appearance in as many issues, we have clematis again. The outer bark of clematis is much coarser than the inner bark we looked at in the last issue, but nonetheless is a useful tinder.
Just to remind you about clematis (Clematis), it’s a genus of around 300 plants that can be found across Europe, North and South America , Australia, Africa and Asia. Clematis vitalba is the species native to the UK, where it’s also sometimes referred to as Old Man’s Beard or Traveller’s Joy. It is a woody, vine like plant that prefers chalk soil (we have masses of it at our woodland on the Kent Downs).
Honeysuckle (Lonicera) is another vine like plant and consists of around 100 species that are found in the northern hemisphere. It’s been introduced to New Zealand where it’s considered invasive. There are also many cultivated varieties that can be found in gardens.
It can be mixed up with clematis, although honeysuckle tends to spiral around itself as it grows and the outer bark is smoother and more paper like.
Next issue I’ll discuss fungus as a tinder. Until then, get out and practice!