Fergus Drennan’s ash bark tubing branch collection method.

Exploring the birch sap branch collection method as a means to refine and perfect best sustainable practice.

It’s  1st April and time to be foolish, to get out in the woods and explore an idea to the deep marrow of ones obsessional satisfaction.

The first time I tapped a birch for sap was over 20 years ago now.  Perhaps it was my timing – I’m not quite sure; with the passing of time my memory has become hazy, but I was naturally drawn to the branch collection method: attach tube to the cut end of a branch, run it down into a bottle and collect about a litre of sap in 24 hours. That was the theory at any rate. In practice, for me, 20 years ago, it simply didn’t work. Perhaps I cut the branch too early in the season or too late – when sap flow wasn’t adequate; I can’t remember? What I do remember is that on subsequent years I switched to the drilling of the main trunk method. I’ve never been entirely comfortable with it, for a number of reasons……

I won’t go into those reasons here, but will encourage you to read the best book you’ve never read. In the past two months I’ve read two sublime books by the painfully insightful and magical weaver of metaphors, Chris Arthur (he was my favourite lecturer at university 15 years ago, teaching Buddhism, and Religion and The Media). In Words of The Grey Wind, in his essay ‘Mistletoe’, he describes how that “vegetable vampire” suckles from a trees intricate tubing of xylem and phloem, pushing its “unfolding tendrils into the sap-filled heartwood of [its] living perch, merging with the nerves of apple, willow, lime and stealing from them whatever [it] need[s] to flourish…..It  may only rarely bleed them dry, but its hold is deep, tenacious, predatory…… Mistletoe  bites its prey like some stealthy, ligneous mosquito, then extends its feeding tubes into the host’s living substance and sucks from there the rich juices of the tree’s vital pith”!

Enough Chris Arthur! Yes, in relation to my aggressive birch tapping, for the past 20 years, I too have been acting like a predatory and vampirous mosquito! And, what is worse, I am creating other vampires. Only yesterday, I received a message from some vampire calling himself Tim The Tapper. He told me how, following my blog instructions, he had tried to tap a tree – unsuccessfully, describing how it was left “weeping sap”. Weeping! Enough!!

……… Then, last month, in the first issue of the new on line magazine The Bushcraft Journal, to which I had contributed an article mentioning birch sap collection (the main trunk drill method), I also saw an article by John Ryder. John Ryder, to his credit, is one of those people you can have confidence is speaking from experience – not aspiration, wishful thinking…or, simply, bullshit! He wrote about the plastic tubing branch collection method of birch sap collection. I was inspired by John, not only to give it another go, but to really embrace the spirit of bushcraft, and explore how it might be possible to fully take the process towards radical sustainability, that is, using 100% wild crafted materials (and using 100% wild crafted tools). This might seem like an absurd ideal, a pain in the arse, just simply too much effort – after all, plastic bottles and tubing are easy enough to come by. That’s true, but I had also been thinking about my friend Mark Boyle’s POP model (POP: Progression of Principles). He talks about this in terms of progressing to a money free economy (one based on love, respect, connection and reciprocal understanding), but the POP model has relevance in countless situations. In my case, it was a useful template to reflect on moving from my current birch sap collection methods to a more bushcraft/nature/natural materials based technique. But I’ll let Mark explain, as he describes it so well:

“Non-monetary economics is not prescriptive – take what suits your purposes and leave the rest. You may want to be moneyless simply for food, or for your shoes, aphrodisiacs or soap. You may just want to travel overland to a cave in Turkey without needing a penny, make your own drum out of a roadkill buck, or produce all your own booze. It was in recognition of this that myself and Shaun Chamberlin, Transition Town Kingston co-founder and author of The Transition Timeline, devised a mechanism called the Progression of Principles (POP) model to help us all on our individual paths. It allows you to make a transition from the economy you live within now (the global, exchange based economy) to whatever economy you would like to be in (which for me is a localised gift economy), progressing with the speed and urgency that feels appropriate to you.

The model is created by you, for you, and there is no ‘right’ or ‘wrong’. For example, my ideal for transport is to walk barefoot, feeling the dew beneath my feet as I tread carefully amongst Nature. But in reality, I’m up to my neck in work. Therefore at the bottom of my personal POP model for transport is where I am now – a bike salvaged from the detritus of industrialised society, in the middle a pair of clogs I made from local wood or a pair of cast-off trainers, and at the top barefoot walking. Using it I can then commit to designing my life in such a way that in two / five / seven years I’ll have made my way to a point where my actions reflect my beliefs, and where my spirituality is applied in the litmus test of the physical world.”

Thanks Mark. This is a really useful way to focus ones thoughts and intentions, especially for someone like myself who is often overloaded with ideas, to the extent that things can become quite chaotic!

So, my thoughts turned to how it might be possible to replace plastic tubing and plastic bottles with natural materials, and yet still be able to collect sap simply and efficiently.

Of course, in such situations, ones thoughts turn to the great Mcnutt (aka Ben Mcnutt of Woodsmoke – or perhaps it was his equally great partner, Lisa). I can’t remember who it was, but one of them kindly showed me how to make poachers whistles from green ash some years ago. This is a really fun thing to do (kids love it); it’s very easy, and like so many bushcraft techniques, the simple skills learnt can be applied in different situations.

If any of you have made poacher’s whistles, you’ll know that at this time of the year when the sap is also rising (but not in tappable quantities) in ash trees, 6 inch lengths of hollow bark tubing can be made from 1/2 – 2cm diametre lengths of green ash. On a hard surface, the bark is tapped with a smooth hard stone up and down its length on all sides. If done properly, this loosens the bark without splitting it such that, gripped firmly and given a sharp twist, the whole outer bark tube can be released and removed.

My idea was to build up a large length of tube using as long individual tube sections as can be made, and binding the sections using birch tar and plant cordage (or – externally bound using birch polypore strips). The tube would lead down from the branch to a birch bark or deer stomach (birch tar waterproofed)  collecting vessel (or perhaps a simple birch bark container).

And, unusually, I have the pleasure of reporting that it worked a treat, exactly as I imagined. However, as I left my front door on the way to the birches, I  intently observed the qualities of the materials around me – especially for tube like qualities (good length and hollow or easily hollowed stems). Before leaving the garden I had collected pampas grass stems, and thin strips of paper birch bark. Then on my walk to the woods I discovered dried out Japanese Knotweed canes, dried out hogweed stems, dead elder branches, and an abundance of dead bracken, birch polypores, sticky cherry resin, and bluebell bulbs (all of these worked to produce tubing, although some where simpler to use than others).

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It had been my plan to use the thin pore surface of these as a binding wrap to hold together sections of natural tubing. This worked, but not quite as I imagined. In September and October when the fungi are still maturing the tube layer is about 1 mm thick. At that stage it can be cut in strips and wrapped around the finger as a sticking plaster. It stretches well, and the heat from your hand dries it further, helping it to really grip the finger. Of course, in March/April, that layer is now mature and 1/2 cm thick. It doesn’t bind in the same way. However, if you find specimens that have not dried out, thin sections can be cut from the main fleshy body of the fungus. These are not quite as elastic as the immature pore layer, but work well as binding wraps with a little care. Some I wrapped simply by binding and holding over hot embers for 15 mins, some I stuck with birch tar, some I stuck with cherry resin, and some I stuck with chewed up sticky bluebell bulbs (also drying over hot embers).

Of course, you could simply just  make cordage out of various things, and use that for binding. That would be both practical and sensible, on the other hand, I find birch polypores endlessly fascinating, so am always exploring new ways to get to know that mushroom’s qualities and uses………

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This (above) was my most ‘bushcrafty’ method: Top end: ash tube connector (stuck with birch tar), Japanese Knotweed cane 9the nodal cross-sections are very thin and readily broken by pushing down a suitable stick). Bottom end: birch polypore strips and a bark tanned stag’s bladder – 750ml capacity (outer surface rubbed with birch tar – not actually necessary). It sits full and fat on a birch bark hoop.

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Above: Using bracken stems. At first I tried to hollow these out, but then realized it was much quicker to find ones that had hollowed naturally. The upper binding is paper birch bark and birch tar. The connections are bound with birch polypore stripe using all the different sticking techniques mentioned.

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Detail of birch bark and birch tar binding.

birchtubing 032Just over 1/2 litres collected in 24 hours.

Below: I ran out of tubing, so had to ration what I had. Actually, you don’t need much per bottle, as long as the bottle is secure. 4 litre bottles with a handle are great, because you can tie the bottle with string from the handle to the branch, so that even though it may fill and be heavy with birch sap, it will not fall down.


Below: High branches can be pulled down using whatever is to hand, in this case a useful branch.

Below: Smaller bottles such as this 1 litre one don’t need tying if the hole where the tube fits in is sufficiently tight,

So where is the picture of ash bark tubing? In that most annoying of camera sentences: “Please replace battery”…………

Note: this article is a a link from a more general blog about birch tapping:

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