formed higher in the crown of the tree and the formation
of a bark-included junction lower down in the tree. This
is because the junction is being held near-to-static due
to these naturally-occurring braces forming above it.
The finding of this association has quite a number of
significant consequences for tree assessment, tree
pruning, and tree management—too many to cover them
all in this short article. This research finding is also mak-
ing my life very busy, as I have been training hundreds of
arborists and arboriculturists in the UK on natural brac-
ing, and I am giving talks overseas on this topic as well.
The most obvious consequence of this phenomenon is
that, if a natural brace has been in-situ for many years
and has resulted in the formation of a weak bark-includ-
ed junction below it, it would be unwise to just prune
out that bracing branch. And yet, probably due to the
traditional guidance encouraging arborists to remove
crossing, touching or rubbing branches, it is quite fre-
quent for one to see that type of pruning, which results
in the opening up of weak junctions to movement they
have not experienced for years, and they are not really
strong enough to withstand (Fig. 4).
It does not need to be pruning that removes a natural
brace: as a tree grows and develops, a bracing branch
can subsequently be shaded out, die, decay, and then
break. The weak bark-included junction formed below
that bracing branch is thus opened up to movement,
and will be at a heightened likelihood of failure for some
time. In such an event, the response by the tree's tissues
is to rapidly produce dense wood at the bark-included
junction, where the vascular cambium straddles the join
between the two branches (Fig. 4), forming what I refer
to as "bulges" in response to the strains experienced in
that location. It is possible for a tree to repair the fault of
a bark-included junction, then, by producing wood either
side of the bark inclusion, embedding that bark or form-
ing a cup-like union around it. In general, I've observed
that the younger and smaller the junction, the more vig-
orous the tree, then the more likely it is that the repair
Type B
Type C
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