#self-grafting

This tree is an example of a gemel, or two conjoined trees that fused together in a process called inosculation - essentially, self-grafting. This is pretty common in thin-barked trees like apple trees, blackthorn, beech, and olives, but pretty rare in thick-barked Douglas fir trees like this one. This tree has a lot of damage from boring beetles, possibly by Douglas fir beetles, Denroctonus pseudotsugae (I could be wrong, though). Being fused together might have weakened the tree, making it susceptible to beetle attack.