Odd looking pine tree, one branch did not follow the rules?

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Discussion Overview

The discussion centers around an unusual pine tree observed in southeastern Pennsylvania, specifically focusing on a branch that exhibits atypical growth patterns compared to the rest of the tree. Participants explore various hypotheses regarding the cause of this anomaly, including genetic factors, potential species grafting, and environmental influences.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant suggests that the unusual branch may belong to a different species, possibly resulting from a seed germinating in a damaged area of the tree.
  • Another participant compares the growth to mistletoe, indicating a potential similarity in how the branch interacts with the host tree.
  • Several participants reference the concept of "witch's broom," noting that they have seen smaller examples but not one as large as the observed branch.
  • One participant raises the possibility that the unusual growth could be a squirrel nest, which can alter the appearance of trees significantly.
  • A participant introduces the concept of apical dominance, explaining how the suppression of lateral bud growth by the terminal bud can lead to changes in tree shape when the terminal bud is damaged.

Areas of Agreement / Disagreement

Participants express multiple competing views regarding the cause of the unusual branch growth, with no consensus reached on a single explanation. Various hypotheses are presented, and some participants build on each other's ideas while others introduce new possibilities.

Contextual Notes

Some claims rely on assumptions about tree biology and environmental factors that are not fully explored or verified within the discussion. The lack of definitive evidence for any single hypothesis leaves the topic open to further exploration.

Spinnor
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Walking the dog takes me past an odd (to me) looking pine tree. I live in south eastern Pennsylvania. With help of Google I think the tree in question is a White Pine, see

http://www.oplin.org/tree/fact%20pages/pine_white/pine_white.html

Also see the images below of the tree. I don't think I have ever see a tree like this one. It seems one of the branches did not "follow the rules" so to speak. One branch near the top is different from the other branches on the tree in at least two respects. While most of the branches grow outward this branch grew upward and into a large dense ball of sub-branches. It seems that genetic instruction for the one branch were not the same as the other branches?

Any thoughts or suggestions welcome!
 

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That's very interesting. Is is possible that the branch is a different species? Perhaps the tree was damaged years ago and a seed from a different species germinated inside the damaged section, then later began to feed off of the tree like a graft.
 
It reminds me of mistletoe, just bigger and less distinct from the host tree in terms of leaf-shape. Which makes me think that the suggestion in the previous post may have some merit. :)
 
Have you researched squirrel nests? They are tightly-woven leaf-lined balls of twigs that can distort the appearance of trees.
 
turbo said:
Have you researched squirrel nests? They are tightly-woven leaf-lined balls of twigs that can distort the appearance of trees.

The pictures I included above did not give any scale. From the photo below the "ball" of branches it is clearly the size of a car. I think AlephZero hit the nail on the head. Thanks to all! I will now be on the look out for another "witch's broom".
 

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I joined this forum with the hopes of providing an interesting answer to this quest. Unfortunately, I'm now not sure if my answer is correct.

Apical dominance

The "terminal bud" (ie, the top of the tree trunk) produces a hormone that suppresses the growth of the "lateral buds" (ie, the ends of the branches), which causes the trunk to grow vertically and the branches to grow horizontally. And, for example, it helps to produce the typical conifer shape.

However, what happens when the terminal bud stops producing this hormone? For example, a lightning strike might damage or destroy it, as would an insect that ate this tender bud. When this happens, the lateral bud that can produce the most of this hormone becomes the new tip of the trunk, and its branch turns vertical and becomes the new trunk. I am unable to find a photo of this phenomenon, but this silhouette seems to show it about three-quarters up the trunk (it seems to shift to the right). This is what I thought the photos would show. The phenomenon is more obvious with conifers that have whorled branches.

GR05_P_men_v_gla_silhouette.gif
 
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