Thread: leaking Keno
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Old 11th July 2007, 03:27 AM   #7 (permalink)
Ekka
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Join Date: Jan 2007
Location: Brisbane
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Yeah, that's OK

BUT

And I'm going to chuck a red herring in the works.

In most instances where gum trees are protected and home-owners are declined removal by authorities, the authorities throw a token 20% thin to the home-owner. (ignore the deadwood, rubbing diseased etc as that's genuinely needed)

Frankly, on a euc, that 20% thin should be pretty much carried out on the very tips where the leaves are... with secatures or the larger version loppers (I hate that word).

I have used towers to do this occasionally but frankly not often enough (clients dont want to pay the money)

On climbs you may remove a few of the internals but generally, on a euc, you'll just make holes in the canopy and even lions tail the tree.

The irony is that much of the work is needless and pointless ... it's prima facie to relieve some anxiety to the client and believe the tree is somewhat safer. In a few years the tree has replaced that foliage anyway.

Trees only grow on the ends or tips. Those long thin branches typical of our eucs with some cabbage on the ends is what we see break time and time again in winds. Long lever arms, parachute on the end it's bound to happen. The thinning needs to be on those ends. Opening up the guts of the tree for wind to now turbulate where it never has before can load branches that haven't experience or compensated for the new found stresses and perhaps crack or fail.

The issue is eucs generally do not lend themselves well to reduction pruning as most branches are of the same length. You want to reduce a long branch back to the next union (target cut) and that branch is just as long as the one you are going to cut. So we thin them.

Eucs vary their foliage according to conditions, but in a bumper wet year they really bulk it on (stressed eucs can do the same though) if you haven't noticed. So much so that branches bend under the weight ... add some wind a you get failures.

Trees in urban settings often are solitary trees exposed to the full brunt of adverse conditions with man made structures that intensify wind spend unlike natural forests where trees work together. So often in urban yards we have these big eucs which occasionally break branches etc ... sure you can say it's species related failures but more so our ignorance in retention or selection in the first instance.

Just food for thought.
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