From a book titled Canoe Crossings, I learned that what made birchbark canoes so special was that the grain of the bark that covered them was transverse rather than longitudinal. What that means is that the grain ran around the tree trunk it came from, rather than up and down the trunk of that tree. “This,” author Sanford Osler said, “allowed for sophisticated shaping of the bark and superior canoe design. In addition, birchbark did not shrink or expand even when wet; it was smooth, and highly resistant to rot.”
The author goes on to talk about other canoes, however, and has little more to say of the birchbark canoe. So I looked for other sources of information, and of course, dipped into The Writings of David Thompson, Volume 1, The Travels, 1850 Version, edited by William E. Moreau. I thought that David Thompson would have plenty of interesting things to say about the birchbark canoe, and he did: Of the two kinds of birch trees that grow in Canada — the white and the red — “the White Birch is the most valuable, and contributes more than all the others to the necessaries and comforts of life.”
In the Spring the sap, when boiled down, yields a weak molasses; but the most useful part is the Rind, which is peculiar to this tree; the bark is of a redish [sic] color, and good for tanning; this bark is covered with a Rind, its growth in a horizontal, or longitudinal, direction; while that of the Tree, and its bark are vertical.
The Rind he is referring to here is what we call the “birchbark,” which grows around the tree in a horizontal, or transverse (“crossing from side to side,” rather than longitudinal) direction. Thompson continues:
In my travels I have noticed, that the thickness of the Rind depends on the climate; the colder the climate the thicker the Birch Rind. On the west side of the Rocky Mountains, where the winter is very mild, the White Birch is a noble large Tree, but the Rind too thin to be useful for Canoes.
I had always thought it was the size of the trees: that they were smaller in the west than on the east side. But it is likely that Thompson knows more than I do on this subject. And, in fact, when Thompson crossed the mountains, his men had to build canoes from cedar boards because they could not find birchbark thick enough to make canoes from. These boats he built are the ancestors of the Columbia Boats used for so many years on the Columbia River, from Fort Vancouver to Boat Encampment.
In this region few white Birch exceed thirty inches in girth; but in general the Rind is excellent for all purposes and is from two eights to three eights in thickness. It is all marked with what is called cores on the outside of the rind, of about an inch in length, and narrow. When these go through the rind, it makes it useless for canoes. When the Natives see a Birch Tree with deep cores, they say it has been severely flogged by Wee sauk e jauk (the Flatterer), for by their tradition, when the Trees were renovated after the deluge, Wee sauk e jauk commanded them all to appear before him, which order they all obeyed but the Birch Tree, which for disobedience he flogged, of which the cores are the marks.
I love stories like this! They make me happy. I assume, though, that he is talking about the east side of the Rockies in this next section:
The best time for raising the rind off the Birch Tree is the early part of summer. The tree being smooth is difficult to ascend…Having a strong square headed knife, very sharp at the point, in his belt, he ascends the tree to as high as the rind is good, then raising a small strip from around the tree, [and then cutting] in a straight line downwards. [Because] the sap is rising [the Rind] comes off so freely that two persons with light poles keep it to the tree until it can be carefully taken down; it is then warmed and its circular form made flat, laid on the ground, and kept so, by light logs of wood, and thus becomes fit for use. The common length from one tree is from nine to fifteen feet, with a breadth of twenty four to thirty inches. Very few trees yield a greater breadth in this climate.
As the Birch rind is impervious to water, Canoes are made of it of all sizes to thirty feet in length, by four to five feet in breadth on the middle bar. This large size is made use of by the Traders, for the conveyance of furs and goods, and is so light, it is carried by two men. When turned up on shore, it afford good shelter to the Men against rain and the night.
I wanted to know more about the gumming of canoes, however, and I am not sure there is anything said on this subject by David Thompson. Gumming the canoes is a pretty constant chore when you are travelling in them, and the force of the water in the rapids can basically “ungum” the canoe — the Gum is the canoe’s waterproofing. I have to research this subject because I am now writing about a canoe journey where the canoes become “ungummed” multiples times a day! If the men have to gum the canoes, I need to be able to describe how they do it.
Now I do know a few things about the use of birchbark canoes west of the Rockies. First, the object of harvesting birchbark from a birch tree was to take only the outer bark, and not the living inner layer of bark. Once a birch tree is harvested for its bark, it cannot be harvest again for another ten years. So you can see the problem.
By the time Peter Skene Ogden moved north to take over New Caledonia, where he headquartered at Fort St. James, there was little birchbark available in the district around the post. It had all already been harvested. So he built the first boats, or batteaux, that were always on the Fraser River after that. Canoes were still there, but not used in the brigades.
If you want to know a little more about building a birchbark canoe, you can go to this site: http://northwestjournal.ca/ and look around. It’s an old site and hasn’t been updated, but it’s a good one. You will see the link to *Making a Birchbark Canoe* off to the left of the page — but there’s lots of others things to look at.
So, gumming of canoes. “There are three ingredients in the gumming compound,” the author of one of the pages I have collected says. They are: spruce resin, tallow, and charcoal. Most modern birchbark experts agree the charcoal (or ash) can be omitted, but it might well be a part of the traditional recipe. I leave that up to you.
To collect spruce resin, you take a hatchet and make cuts in the bark of many spruce trees during the warm seasons. The traditional method would have you returning two or three weeks later with a canvas bag, collecting the thumbnail sized lumps of sap that have oozed from the wounds. Crop the spruce resin into the canvas bag.
One man who has written about the process of collecting the spruce resin cuts the globs off the tree with his knife, and collects it on a piece of birch bark. “This stuff is sticky,” he says, “So the trick is to try not to handle it.”
Young resin (that hasn’t sat on the tree for a long time) is a bit like cold honey in terms of consistency, he says. This man harvests his resin on the golf course, apparently while he’s playing golf.
So if you are using the traditional method, you have collected the gobs of spruce resin in the canvas bag, and when finished, you can tie the bag securely at the top. Then, drop the bag containing the spruce resin into a kettle of “vigorously boiling water,” and work the bag with a stick in order to squeeze the hot resin through the canvas into the water. The purified resin will float to the surface, and the boiling action of the water will form it into balls. The finished resin, once cooled, is a yellowish crystalline-like substance, with a white frosting.
You can make a different choice today, of course. Another man does not collect the resin in a canvas bag. He collects it in a freezer bag and then pours it out of the freezer bag into a pot, and heats the water up on the barbecue outdoors. He has learned the hard way to not boil the resin on the kitchen stove, as the odour permeates the entire house! With this method, he says it takes a lot of stirring to melt the resin. Then he pours it into a frying pan, filtering it through some burlap to take out twigs and botanical stuff. This sounds complicated! He has to make a tourniquet of the burlap to get all the gum out of it.
Another man warns to not use your own pot to melt the resin, but find one at the thrift store. The reason for this is: You will never get the resin out of the pot, nor out of the frying pan you use. It is pretty lumpy and gross to start, he says, but once the resin has liquified you will need to strain it through an old sheet to remove the debris.
But you haven’t made the gum yet — the resin by itself is far too brittle to be used for gumming a canoe. Place the resin in a frying pan or in a pot that is dedicated to this purpose, and add tallow (suet) and pulverized charcoal. (Omit the charcoal if you wish). Other suggestions to replace the tallow are bear fat, or bacon fat — about a tablespoon is suggested in one case. Another man used lard, again about a tablespoon full.
If you’re going to add charcoal or ash, as the traditional recipe requires, this is the time you do that. Some recommend you do not: if it melts in the heat (and it will), it looks terrible, like tar!
Stir the resin and melt in the fat until the resulting gum is an easily worked mass. Determining the proper mix of resin and grease is a matter of trial and error. One man found that the more he cooked the gum the better it gets, so if it doesn’t work the first time, scrape it off the canoe, reheat the gum, and reapply. (He thought it might have water in it still).
He also said that the finished product — the gum — is like peanut brittle, and it hardens in much the same way. Another man said the gum was a thick amber liquid when ready, and very sticky! A third man says that when the gum is warmed by the fingers, it is plastic and slightly sticky. When cooled it becomes hard and even slightly brittle (like peanut brittle, see above).
To apply, warm the gum (not too hot), and apply liberally to all the birchbark seams on the outer canoe surface. You can apply it with a stick, if you wish, but also with your hands. Saliva on the hands keeps the gum from sticking to them, so licking your hands, or spitting on your hands, is part of the process of applying gum (how interesting!) Work the gum into the seams, don’t just rub it over.
If the mix is right, the gum will flex with the canoe and it will not crack and fall off. If you add too much grease, the sun will melt your gum away. If you add too little grease, you will have cracks and leaks.
It’s even more complicated than that, however. You have to consider the temperature of the water, and the temperature of the air. You typically want a bit more fat below the water line where it is cooler, and less above where the sun will cause temperatures to be warmer. In other words, you are always fiddling with the gum, adding grease or not adding grease, depending on the heat and the weather and the rivers, and whether or not you are portaging.
And, a final warning, do not leave the canoe out in the sun.
The gum itself also takes some maintenance. You don’t however always have to add gum to the mixture. But, if you have a birchbark canoe, you will always travel with some gum so you can maintain the canoe on an almost daily basis. And, I think you should plan on having a tight lid on the pot so you don’t get water in the gum.
Remember, too, to carry extra grease to add to the gum you have.
Here is the final instruction: every time you stop, you gum. Every time you portage, you gum. So, basically, GumB4UGo!
Copyright, Nancy Marguerite Anderson, 2020. All rights reserved.
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