Well here's a picture of the staining in this piece of walnut.
Here's another picture of the same board. This one has a funny story to go with it. The lady I got the tree from assured me it didn't have any nails or hardware in it. Well I'm sawing the log and she proceeds to tell me stories about this tree. She says her daughter used to have a hammock in it. I said great! Then she assured me she took it out. She no longer walked in the house and I hit the very edge of that Eyebolt. Some how that log was just perfect to bury the eybolt in the 2inch slab. The only reason the log was that way was because I hired a rollback to move the log. Well he thought he could just lift it on the truck with a skidsteer. Well something happened and a weld on the bucket broke and he cut his losses and said he wouldn't move the log. I didn't see the damage to the bucket But, I was told it was pretty good. Anyhow he moved it and that was the only reason I didn't hit that eye bolt dead on.
There is no staining because of the plating or maybe the sapwood doesn't cause the staining.