Trees and wind

I was at a presentation a couple years ago in Corvallis, OR where a fellow had that set up on a tree. Very interesting and complex study
 
That wind loading and pull test stuff is trick.

I saw Ken speak once, he showed some interesting examples of the difference in topping a tree with branches and without branches.

Big difference!

The tree with many branches swayed much less.

He showed this vid, sure everyone has seen it.

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Ed Gilman's input:
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The shape of a leaf will change as the wind load increases so that the overall wind resistance decreases.
 
He showed this vid, sure everyone has seen it.

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Ride 'em Cowboy!!!!!!!!!!! Amazing that he stayed up there ain't it? Anybody on here ever done that? C'mon, 'fess up!
 
James' ppt at ISA was the best I've ever seen, and i have seen a whooooole lot. Peppered with vid clips, all flowing to some remarkable observations. Introducing the 4th dimension into arboriculture.

If you get a chance, see him.
 
This is pretty interesting stuff. Thanks for posting the link, Gary.

I have a couple of totally disperate experiences/observations that bear on the subject some:

First, as I spent some 25 years as a reforestation specialist, I was pretty heavily involved with raising conifer seedlings for planting stock. One type of refor stock we utilized was raised in tube containers in greenhouses, just 1 year old at outplanting. By observation, it became obvious that seedlings placed in near proximity to ventilation fans in the greenhouses achieved much greater caliper (stem diameter) than those farther removed from the resulting air movement. This lead to the culture practice of subjecting the whole stock to fans solely to bring those calipers up, which makes for a sturdier stock and better survival percentages in the field after outplanting.
FWIW, :).

Second was my experience as part of the pioneering group of technicians and fisheries biologists developing the technique of rigging and pulling stream-side trees over with cable, blocks, MA, and heavy equipment to achieve in-stream structure to improve anadramous fish habitat.

In both cases, the amazingly varied ability of trees to respond to outside inputs was eye-opening, to say the least.

Wind makes them strong. Their ability to deal with dynamic forces is huge. On the other hand, static pulls proves them to be scary weak.

Consider this in climbing and rigging them, is my advice.
 
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