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University of Wisconsin - Stevens Point

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  Prairie Folklore

by Wayne Pauly from Dane County Parks ACTION Adult Conservation Team Newsletter (All folklore stories)


Oaks and Lightening

You’ve seen trees struck by lightning, but did you notice that some scars are straight, while others spiral around the tree.  Years ago I asked a group of naturalists if anyone could tell my why.  Well, Rick grinned and said, “The lightning coming straight down must have been in a hurry”. 

Actually, it was following water vessels that make up the wood grain --- sometimes the grain is straight, sometimes it spirals.  If you look for lightning scars, take note that oaks are struck and damaged more than any other tree. 

A German rhyme loosely translated said,

            “Before the oaks you ought to back off,

              Before firs you ought to flee,

              But you should seek out the beeches”  

              (P.s. it rhymes in German) 

And in England,

            “Beware of the oak it courts the stroke,

              Avoid the ash it draws the flash,

              Creep under a thorn, it will save you.” 

Scientific research confirms these old legends, for example in a 11 year forest study in Lippe, Germany, oaks were hit 56 times, firs and pines 24 times, and beeches not at all, although the forest was 70% beech trees.  Our ancient European ancestors noticed this phenomenon, and that’s why the Greek hurler of lightning, Zeus, had is oracular oak where his voice was heard in both the rustle of the leaves and the crash of thunder.  Other gods of lightning whose revered symbol is the oak include the Scandinavian Thor with his thundering hammer and the Roman god Jupiter.   

Beeches may avoid lightning strikes because oil in the wood reduces its ability to conduct electricity.  In addition, when struck, it is left undamaged because lightning follows the path of least resistance, and flows outside of the tree in the slick of rainwater on the smooth beech bark.  Oaks, however, have very rough bark that doesn’t wet uniformly, so the path of least resistance is the tiny water filled vessels making up the grain of the tree.  The sudden 50,000 degree temperature explosively vaporizes water in the narrow vessels, blowing the tree apart.

Vascular Plants

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