Dendrochronology

Benson Gray

Canoe History Enthusiast
Staff member
Does anyone have any experience with dendrochronology? The first link below has more details if you are not familiar with dating wood from tree rings. This might be a way to help date some of the very early canoes. It can be done with musical instruments as described at https://violin-dendrochronology.com/ so a huge amount of wood is not always required. The second link describes the use with old barns but they generally have much larger sizes of wood to work with. The last link indicates that the cost can be "about $2,000 per analysis" so it is not inexpensive. Thoughts?

Benson




 
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Interesting links Benson. Deserving of further study. The Eastern Barn Consultants are sort of in my back yard... and, I have an old Pennsylvania German bank barn where I do my canoe work/fun! Thanks for posting this.
 
My folks had a dendrochronologic study on their circa 1750s house. The core was about 1/4" in diameter and 6" or so long. They had several cores done, but only one or two were conclusive (and helped confirm the date the house was built. The core is taken on a timber with a waney edge towards the pith - the waney edge is required to know when the tree was harvested (e.g. no growth rings were removed in squaring the timber). The method also requires regional reference trees with which to establish a connection. The reference tree is harvested at a known date, so that the age of the tree is known and the rings from a core can be cross-matched.

I took a quick look at the violin aging page, but it isn't clear how the establish the reference to know when the wood was harvested. Being radially split, at least the growth rings can be easily analyzed.

I suspect there are not enough bits in a canoe to offer up a decent size sample, and there may not be any references available.
 
Well, this rabbit hole has turned out to be deeper than most. The article at the first link below describes the use of digital photographs to date a violin. The second and third list organizations that work in this space. Now we just need a very old canoe with unusually wide planking and a few thousand dollars to see if this will work.

Benson




 
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Not that I have a spare "few thousand dollars", but what is considered unusually wide planking? This 18' Whistle Wing has 6" sheer planks.
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what is considered unusually wide planking? This 18' Whistle Wing has 6" sheer planks.

This is a good thought and six inch planking could be enough but quarter sawn would show more of the annual grain pattern. It might also be nice to start with an older canoe.

Benson
 
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One of the struggles with this technique is getting good dated reference sources. There are a few old canoes with likely dates that may be able to help. The link below describes one that was probably made in 1901. It has a roughly five inch plank that is quarter sawn as shown in the picture below. It is slightly curved which isn't ideal but might be a good start. Does anyone else want to share a similar picture and details? Thanks,

Benson




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why not trying to ask the question on AI ? in France sending picture is not avaible now ... the new toy of the world and it's free ...
 
why not trying to ask the question on AI

My limited experience with AI indicates that it can occasionally help with general questions (like the previous message that you deleted) but has limited utility with very specific ones like this.

Benson
 
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The early White I am restoring currently has some that is 8.5 inches.

Can you send a picture of the planking like the one of the Indian Old Town above? I may be able to match it up and show the relative difference in years if there is an overlap in the patterns. Thanks,

Benson
 
Zach has provided some additional images with more detail and Chris Pearson has offered to take pictures of his oldest canoes as well.
The paper about the Natural disturbance and stand structure of old-growth northern white-cedar (Thuja occidentalis) forests, northern Maine, USA at the link below probably indicates the best source of information about the northern white-cedar that was commonly used for the planking on these canoes. The primary author also teaches a course on dendrochronology at the University of Maine so I have sent him a message asking if he has any suggestions about how to best proceed.

Benson


 
Progress is being made. I've been directed to Bill Flynt who has lots of experience using dendrochronology to date old houses and is interested in helping to see if this can work for canoes. The current investigation is focused on finding a way to get a very high resolution image for him to work with. I took the cover off my scanner and tried using some pillows on a thwart to push it into the hull as shown below. The laptop was balanced on a step ladder for the 15 minutes it took to scan. This produced a 2400 dot-per-inch image but the focus was terrible so that probably won't be the solution.
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The next tests involved a camera on a tripod with either a flash or ordinary lighting. This had much better focus but less resolution. The flash tended to wash things out so that probably won't work either. The next alternative would be to remove the planking so he can study it under a microscope. This could work for canoes that are being restored but would not help with most other canoes. Small steps,

Benson
 
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To reduce and possibly eliminate the flash/lighting glare, try using a Diffuser, sort of like a lampshade. Another way might be to use a reflector. Anything that makes the light less directly aimed at the subject should help...
 
It has been a valiant effort but the answer to the original question seems to be no, it is not likely that dendrochronology can be used to date the varnished planking of a restored wooden canoe. It appears that the sanding and varnish work on the interior of a wooden canoe are not quite up to the standards of an antique violin. The two pictures below show the rings from my canoe under a microscope and an example of the quality that is commonly required.

This concept might work for a canoe that is being restored which has an unusually wide quarter sawn plank with good grain. The plank will need to be sanded down to a 600 grit, and either photographed or delivered to someone like Bill Flynt to analyze. A one-to-two-inch-long piece is all that would be required. A very high-resolution scan or photograph of the plank's grain might also work. This still might not produce useful results if the plank happened to come from the center of an unusually old log. Bill has kindly offered to do a pilot project pro bono to see if it can work, but future projects are likely to cost over a thousand dollars depending on numbers of suitable samples. Let me know if you want to proceed with a project like this. Thanks,

Benson


Canoe plank photo.jpg
Core photo.jpg
 
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