They can die from all over...Conifers anyway.
Root rot, a rot that starts in the root structure and goes into the stump and up the tree. Not the tree you want to find out about when your starting a dutchman
Top rot can start when the top of a tree is sheared or broken off, weather in bird holes, bugs, ect.
Pocket rot usually starts around snowbreak and/or a big spike knot, also known as a Coon D i c k by old timers. This rot never goes up,always down.
Not sure exactly what it is properly called, but the bud worm lays it's eggs and the new larve eat the fresh growth emerging on Fir.
Mistltoe is a disease that causes the bows of trees to get a real sick look and they grow in clusters at times trying to fight off the disease, essentially producing more growth to combat the dying. I'm not sure how mistltoe is started or what it is....SLOWP!!!! Chime in :hmm3grin2orange: