The power company did some trimming across the road and, of course, I scarfed up as much as I could. It was mostly young black walnut and some black cherry. After cutting and splitting I noticed the split faces of the walnut turning blue-green. Sap reacting with the air? These were very young trees, hardly any heartwood, mostly white sapwood. Can anyone explain what might be going on chemically to create this color?

![[Hearth.com] Blue walnut [Hearth.com] Blue walnut](https://www.hearth.com/talk/data/attachments/129/129791-9ac31526ef2625850d5b1bc4c0a8c72a.jpg?hash=LzDjKj3TKx)
![[Hearth.com] Blue walnut [Hearth.com] Blue walnut](https://www.hearth.com/talk/data/attachments/129/129792-e80b5f0bd597c583d5f7249c16ecd402.jpg?hash=kJYBAVsnxu)
