ENTS, The partially broken Atlantic White Cedar that I photographed nearby last Fall has spiral grain. Most do not, and I don't think I've seen a broken cedar before. I'm wondering if the tree broke because of the spiral grain?
--- On Mon, 5/4/09, Edward Frank <[email protected]> wrote: From: Edward Frank <[email protected]> Subject: [ENTS] Re: Louisiana Live Oaks #2 To: [email protected] Date: Monday, May 4, 2009, 3:37 PM ENTS, Larry, Don, I have seen the same spiraling pattern in a wide variety of tree species. None of the explanations presented in the article make much sense to me. They have not even demonstrated that trees tend to spiral in one direction more than another. There is no common point of reference to say which direction the tree is spiraling. If a tree is spiraling clockwise as looking down at it from above, then looking at it standing the grain would go upward to the right and down to the left. The first thing to do would be to note the species of the tree, the location, and direction of spiral, Once you had a decent data set, then some analysis of the information could be made. If I were to guess, and it is a guess, I would think the spiraling pattern is a genetic trait and not one developed on the fly in response to average wind direction ad the direction of the sun. Certainly it is not related to the Coriolis effect on something as small as a tree trunk. My guess as to why the tree grain spirals is that it is to provide additional flexibility in response to wind stress, I think the twisted grain would be stronger in response to a wind than would a straight grained tree. The tree tends to twist in response to winds rather than snap. There is no single direction of weakness formed by the structure of the parallel grains, every direction is equally strong with the grain spiraling around the trunk. The spiraling may not be in every specimen of a tree depending on its own genetic make-up and could require some triggering stress to develop. We need some field data and a structural engineer to look at the mechanics of the spiral grain. Ed Frank ----- Original Message ----- From: "Larry" <[email protected]> To: "ENTSTrees" <[email protected]> Sent: Monday, May 04, 2009 6:16 PM Subject: [ENTS] Re: Louisiana Live Oaks #2 > > Don, That is really a great Question, I noticed several Live Oaks > that grow in this pattern. Ed, Bob,Will, et al, have discussed this > before, to be honest I'm not sure. Maybe in its youth it began to > sprial from storms, etc. I found this, check this out, its way > cool! http://www.gi.alaska.edu/ScienceForum/ASF7/783.html Larry > > > > --~--~---------~--~----~------------~-------~--~----~ Eastern Native Tree Society http://www.nativetreesociety.org Send email to [email protected] Visit this group at http://groups.google.com/group/entstrees?hl=en To unsubscribe send email to [email protected] -~----------~----~----~----~------~----~------~--~---
