ArboristSite.com Sponsors


What causes or caused this change in angle in the trunk?

ATH

Addicted to ArboristSite
Joined
Nov 18, 2006
Messages
4,183
Location
Ohio
40 yrs was just a random #. Plausible. Depending on site and species could be 20 or 200 just as easily.

For the white bark:
Imagine the "back" is a cylinder attached to the "body" and the "arms" as a separate cylinder attached on the bottom side. What part of those cylinders is most exposed to things rubbing against them (knocking bark off)? Not the underside or top side, but the parts that stick out to the sides the furthest. That is where the bark is exfoliating as expected.
 
tree_enthusiast12

tree_enthusiast12

ArboristSite Lurker
Joined
Jan 9, 2021
Messages
20
Location
United States
40 yrs was just a random #. Plausible. Depending on site and species could be 20 or 200 just as easily.

For the white bark:
Imagine the "back" is a cylinder attached to the "body" and the "arms" as a separate cylinder attached on the bottom side. What part of those cylinders is most exposed to things rubbing against them (knocking bark off)? Not the underside or top side, but the parts that stick out to the sides the furthest. That is where the bark is exfoliating as expected.
Ah, this still doesn’t make sense to me sorry, but I think i know where my confusion here lies now.

The white bark is the new bark, not the old bark, no? The original bark would be dark, so isn’t it exfoliating on the top side of the cylinder more (where the “back” would be)? Notice it’s completely white on the top side of the bend meaning the old bark has completely gone away (apart from the brown circle). Meanwhile, on the sides where the “arms” are, it has partially exfoliated into white marks but not fully, no?
 

Rabid K9

ArboristSite Lurker
Joined
Apr 29, 2019
Messages
33
Location
Western Australia
Am very familiar with the species (Corymbia maculata).

Moderate to fast growing hardwood, wide natural distribution, valuable tree commercially with a variety of heavy structural uses, timber achieves a high BAL (Bushfire Attack Level) rating, so still able to be used externally for construction. Still used for power poles in certain areas. I have a stack at my yard salvaged from jobs that will be sold as 'bush poles'.

The morphology of that particular specimen is very common, certainly not restricted to the species & the likely reason of it's development have been explained here already. Will commonly see this type of structure a number of times within large spotted gums (spotties for short), with some impressive compression ribs & other feature even on relatively young trees such as this. Would estimate tree age to be <35 years, in this situation, tree as an indigenous marker is not plausible. Directional & territorial trees were marked differently & could walk you directly to many in some of our remoter regions.

Photos showing some thinning work in mixed plantation of spotted gum & red stringy bark to give an idea of growth rate. Was planted 1995, average side conditions, poorly managed (as a timber resource) since then.
 

Attachments

  • Plantation 1.JPG
    4 MB · Views: 9
tree_enthusiast12

tree_enthusiast12

ArboristSite Lurker
Joined
Jan 9, 2021
Messages
20
Location
United States
Am very familiar with the species (Corymbia maculata).

Moderate to fast growing hardwood, wide natural distribution, valuable tree commercially with a variety of heavy structural uses, timber achieves a high BAL (Bushfire Attack Level) rating, so still able to be used externally for construction. Still used for power poles in certain areas. I have a stack at my yard salvaged from jobs that will be sold as 'bush poles'.

The morphology of that particular specimen is very common, certainly not restricted to the species & the likely reason of it's development have been explained here already. Will commonly see this type of structure a number of times within large spotted gums (spotties for short), with some impressive compression ribs & other feature even on relatively young trees such as this. Would estimate tree age to be <35 years, in this situation, tree as an indigenous marker is not plausible. Directional & territorial trees were marked differently & could walk you directly to many in some of our remoter regions.

Photos showing some thinning work in mixed plantation of spotted gum & red stringy bark to give an idea of growth rate. Was planted 1995, average side conditions, poorly managed (as a timber resource) since then.
Interesting, did not expect an Aussie to chime in, cheers. When you say you've seen this particular morphology, do you mean that you've seen it bent in that manner? This is (or was, since it is now cut down) in New South Wales in Bengalee Scout Camp in Nowra, Australia by the way. From what I know, it is near an Aboriginal area, hence was wondering whether it's possible it was bent by them. You said aboriginal marked trees are marked differently. Where have you seen them? Anecdotally, I have heard stories of Aboriginals bending trees that looked similar to trail marker trees from North America in Queensland. This particular specimen does look like a trail marker tree from North America, and so wanted to ask why exactly it's not plausible that this might have been shaped purposefully.

Do you have any thoughts on the abrupt angle change on the bottom right side of the trunk by the way as discussed a bit earlier on this thread?
 
Top