Hi Bill. Yes, very high temperatures are generated in wood chip piles. A pile of green wood chips this size, with a high moisture content, will heat up to compost pile temperatures.
I used to do a lot of volumetric calculations using photogrammetry for the wood products industries. We’d capture stereo aerial photography of huge chip stockpiles and log decks for Weyerhaeuser, International Paper and numerous other wood products companies in the pacific northwest. From these images we’d calculate their onsite inventory of wood products.
Some of these chip pile were truly enormous and generated a tremendous amount of heat. When conditions such as: wood species, moisture content, height of pile and good old oxygen came together sufficiently, the pile would spontaneously combust.
One such tremendous pile, as my feeble memory recalls, burned for a couple years. I think it was an International Paper mill in Springfield, Oregon.