Checking the middle of the tree

[Larry]

Couple of questions.

I am well acquainted with utility poles.  Just because a pole is hollow does not mean it needs to be replaced, as most of the strength comes from the outside couple of inches.  Would this be the same for a tree?

When some of the tree service outfits find a hollow tree they want to fill em up with re-bar and concrete.  I sorta suspect this hastens the demise of the tree alone with being hard on my chain when I take it down. ??? :( >:(  Comments?

[Phorester]

Yes, it is the same for a tree as a hollow utility pole.  Maybe even more so because the tree is still alive and will contribute new wood every year on the circumfrence of the tree, thus increasing it's strength.

Concrete and rebar was once an accepted practice to "strengthen" a hollow tree many decades ago.  It was found, however, that concrete doesn't bend and sway in the wind, as every tree does.  Therefore, a tree with a concrete plug in it will eventually crack around the concrete as the tree moves and the concrete doesn't.  So in the long run, concrete in a tree will actually cause the tree to weaken as it splits and cracks apart around the concrete.

[Phorester]

ANDYHIX,  I agree with your opinion of ISA certification.  I'm also an ISA Certified Arborist, and am impressed by the entire certification process.  The initial certification test was one of the hardest tests I've ever taken.  The requirement of continuing education credits every 3 years adds to the integrity and credibility of the designation.

Anybody in the tree service business should become certified by ISA, then promote the heck out of it.

[Andy Henriksen]

Larry, for trees, assuming no other defects (cracks, etc.), a tree is considered sound if there is at least 1" of shell thickness for every 6" of stem diameter.  i.e. 1/3 of the diamter should be sound wood.