Figure 4: The Inexplicable. My research into natural bracing
may well be the best contribution I will ever make to our
understanding of trees as living structures. But even within
the niche topic of natural bracing, there are still further areas
to research. For instance, I've observed that there seems
to be a link between initial natural bracing of two stems in
a tree and their eventual fusion together at a later stage
of the tree's development. Trees have a "posture control"
system that orientates their main stems and branches
in an appropriate way (see Clair et al., 2019). It appears
that natural bracing can interfere with a tree's posture
control—and this can lead to fusion of branches, limbs, and
stems that would otherwise have remained separate.
Pictured is what seems like an unlikely outcome: a young horse
chestnut (Aesculus hippocastanum) in a park has formed a
natural brace between two of its upright branches and, within
ten years, these have fused to become a single stem. This may
seem bizarre behavior, but this fusion has acted to stabilize
what would otherwise have become an unstable structure.
Although the experiment would take some time, I think it may
be worth proving that natural braces in trees are associated
with the fusion of stems set below them. This would help
to explain why, upon occasion, when putting a tree's stem
through a sawmill, there can be long vertical sheets of included
bark found inside. Always nice to have an explanation.
"This may seem bizarre behavior,
but this fusion has acted to
stabilize what would otherwise
have become an unstable structure."
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