Lightning and Trees Why when lightening strikes a tall pine tree
it creates a clockwise spiral around the outside of the tree. I
think the the electrical circuit between the cloud and the
ground interacts with the earths magnetic field causing the
charge ions to spiral and this charge going up and down the bark
causing the disruption I see on the bark. The earth's magnetic
field is much too weak to affect lightning. More likely, the
pine tree has a natural twist in the grain. This could cause the
lightning to follow the twist as it follows the lowest
resistance path of sap to Argonne National Laboratory That is an
intriging theory about the spiral track of lightning. I'm not
aware of any investigations into this area. Studies have shown
that lightning follows the path of least electrical resistance
through the air, and that magnetic field effects on ionized
particles exist at much higher altitudes than the region of
convective weather occurrences. Here are a couple of links that
discuss lightning formation an