High Sierra Topix

About 2/3 of the way up to Avalanche Pass from Roaring River, just off the trail were a bunch of lodgepole pines that had sheepherder carvings. One was a carving of a boxer posing with the words carved Liteweigth Champion of the World, Another was a family of duckbilled creatures with the words,
sent from home without food or Clothes. The one below needed no words...

I never see carvings like this.

There is a long history of sheepherder tree carvings in the Sierra and across the West. The lonely men would mark the time and provide commentary on their lives by carving arborglyphs, mostly in the living bark of aspen trees. While aspens can last for >150 years they generally don't and so these carvings are being lost due to eventual tree death. There is even a reputable Kit Carson 1859 signature in an aspen in Colorado.
A great book on the subject is "Speaking Through the Aspens: Basque Tree Carvings in Nevada and California". There are many examples from around Tahoe.
I have a professional interest in this subject (bark carvings, not tree porn) and would be very interested if anyone has repeated photographs of carvings. I'm interested in how the trees grow.