The Un-huggables
The trees in this project are only those that are so big a single person cannot reach around the trunk - well over 100 years old. Where are they on Wolf Ridge property? What can they tell us about the land? There are other questions.
Let's chart where the "un-huggables" are growing.
Comentários
Great to see all these tree observations collected! As someone who studies tree dimensions I would like to make a constructive criticism of the project's premise, however. Tree size is a very poor indicator of age. White Pine is a swift-growing species and can reach "unhuggable" size (around 6' in circumference for most people) in far less than 100 years in the project area's climate. Some of the trees in this project are visibly quite old, but others may be well under a century in age. The project's framing that pines big enough to be unhuggable must be well over 100 years old reinforces popular misconceptions regarding tree age (such as websites that claim to tell you how to calculate a tree's age from its diameter). I feel it would improve this project's educational value to emphasize the size component without attempting to connect it to tree age.
I fully recognize that a tree's dbh is not a perfect proxy for age. I'd like to see some data, though, that would strongly support your suggestion about them NOT being 100 yrs old or older. We are about 2 feet to bedrock and our climate - on the northern edge of Lake Superior - is more harsh than might be a reality even a few miles further inland. For example, night-time temps during the growing season are much lower here than further inland. I suspect that makes it harder for some of these trees to grow as they turn off and on and off and on as the conditions demand.
Can you direct me to some of the research you would reference? I don't deny the possibility that you might be exactly correct, but I'd like to challenge your assertions just as you properly have challenged mine.
Thanks for the challenge. I look forward to learning more. I am glad you found this.
Joe Walewski
Wolf Ridge Director of Naturalist Training
I'll do my best to find something cite-able. My main reference is in my own experience measuring and documenting white pines in the Adirondacks. I would suspect that the growing conditions there are reasonably similar, and emergent white pines in regrowth along rivers and lakes dating within the 20th century are often over 30"dbh and 120' in height. Could we agree that "unhuggable" on average would be around 23"dbh (requiring an arm-span a bit over 6' to hug)? Maximums for old-growth specimens in both regions are similar.
Just to clarify as well- my contention is not that they are unlikely to be 100 years old at 23"dbh, but that they don't have to be over 100 years old to reach that girth. The flip side of course is that they could be 200 years old at 10"dbh in particularly harsh spots (there are even specimens in my home climate that fit that bill).
Will get back to you with some non-personal sources. Glad you're tracking these trees!
I'm having a very hard time finding literature sampling age and dbh in your area or proxy climates (or even low-index sites in the adirondacks). The most useful I've found so far examines old-growth pines at Dividing Lake in Algonquin. A tree growing at the maximum rates observed in their sampling would take almost exactly 150 years to reach 23"dbh. https://www.researchgate.net/publication/263768717_Age_size_and_regeneration_of_old-growth_white_pine_at_Dividing_Lake_Nature_Reserve_Algonquin_Park_Ontario_Ontario_For_Res_Rep_131
If your site growth conditions are more similar to Algonquin than the central Adirondacks, this would support your premise. However, as all of the trees in their sampling are over 250 years old, this may bias their calculations towards providing a slower growth rate as observably growth ring widths at dbh tend to narrow as trees grow older and develop a less tapered and more cylindrical stem form. I'll keep looking around for relevant literature. This is certainly an interesting question to be pursuing!
You're awesome! I really do appreciate the challenge and I certainly do agree with your personal stories. Though it all makes perfect sense, I want to remain a skeptic for at least a few more weeks. I never took dbh of the trees... just tried to hug them. Are their other meaningful pieces of data I could gather for each tree? I think that I might have to head out on adventures this winter to get that data, whatever it may be.
Though my head says to agree with you and move on, my heart wants you to be wrong... ha ha. Later this weekend, I am going to take some time to read that Algonquin work. I am also going to see if I can dig up something... maybe I should reach out to the good folks at the Superior National Forest ranger station nearby. Duh!
Joe
I'd suggest that collecting DBH, categorizing as "emergent" vs "codominant" (as in, what is its relationship to the mixed canopy of other tree species), and making sure to take a photo of the bark on the lower trunk would improve your data. I notice a lot of the observations in this project have single photos looking up into the crown. The condition of the bark on the lower trunk and presence/disappearance of old branch scars can tell you a lot. For example this one is obviously an elderly tree: https://www.inaturalist.org/observations/4616727
On the other hand this one is visibly much younger and I would suggest may be less than 100 years old: https://www.inaturalist.org/observations/4616734
Even if these two trees had the same height and DBH, their bark development and crown structure speaks volumes about the ways that they differ.
On the occasion that there are branch scars and stubs almost all the way down the trunk, you can even make a rough estimate of age by counting how many nodes are visible (White pine produces one whorl of branches per year of growth).
If you can get yourself a laser hypsometer you can also measure height- some models like the Nikon 550 and forestry pro, or Trupulse products have a mode that calculates height correctly (usually designated either 2-point routine or VD mode). The designated "tree height" modes (and traditional height measurement with a tape and clinometer) incorporate some geometric errors that are not consequential for industry use scaling timber for market, but can create large errors measuring older trees with uneven crowns (definitely a bigger consideration for collecting scientific data). A thorough overview of all considerations for height measurement (and selecting the correct point for DBH measurement in mixed terrain) is covered in this handbook: https://www.americanforests.org/wp-content/uploads/2014/12/AF-Tree-Measuring-Guidelines_LR.pdf
I have a project page (it's been on the backburner and admittedly needs a lot of work still) collecting observations on iNaturalist of trees that have been measured in accordance with the standards laid out in the handbook I linked, and if you make any such observations (whether DBH only or DBH+height), I'd love to add them to that project as well: https://www.inaturalist.org/projects/nts-measured-trees
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