I worked in an area up in the cascades in washington state that had a lot of mineralization. It attracted lightning strikes so a rather large number of trees were scarred similar to your picture. Spirals, straight streaks, splits etc. Closest i came to getting hit was while working in that area, approaching the edge of a drop off when everything turned white and very load noise. Didn't remember hitting the ground, but i got up and walked over to the edge and saw a big ponderosa probably 100ft tall, had been splintered. It looked like someone had blown it up with dynamite lengthwise. My ears range for several hours.