Staining in Cherry

[Gene Hintze]

Recently turned some Cherry bowls from wood that has been sealed for about 9 months. There is a fair amount of dark blue/grey/black staining in the wood. Any ideas what that may be?

[Cheryl A. Prince]

I just turned some cherry that had the same type of staining. I was told that it is what's left of nails that were driven into the tree years ago.

[Quinn McCarthy]

Did the staining turn up during the drying period?

Quinn

[Gene Hintze]

Quinn,

No, I could see the staining in the rough outs before they went into the DNA

[Erik Johanson]

I may be newbie to some of this but some fungus' leave behind this type of coloration after they have infested a tree, I believe it is called Blue Stain Cap. If I am correct this sometimes creates a very attractive look (to some) and if done carefully can be done to add character to a piece IMHO. I think this is also referred to as spalting but I could be totally off at this point. Here is a link - http://www.sawmillcreek.org/showthread.php?41092-Spalted-Turnings (http://www.sawmillcreek.org/showthread.php?41092-Spalted-Turnings)- from a previous SMC post that has pictures posted of some spalted turnings, is this similar to your staining and discoloration. The nail theory is also a possibility, but if it was all the way through and not localize I would think that the fungus would be more your culprit. Just a guess though. Hope this helps.

[Jim Burr]

Maybe mineral staining?

[Nathan Hawkes]

If the stain runs along the grain, it is mineral staining that moved up the tree as it grew. Cherry does contain tannic acid, and will react to iron similar to oak. If the stain is under the bark, I think this is pretty common in cherry that has been down for a while. (as in not standing). I cut a lot of box blanks last year which had quite a bit of the blue/black color you're describing. I know in my case that I just plain left the logs sitting too long. I had put mine up on blocks so that they were off the ground, but they sat for a good year (sealed ends the day they were cut down) before I got to them. I won't do that again. It wasted quite a bit of usable wood.

[Gene Hintze]

Nathan, Thanks for your post. I think that is what I have here. Nice form, excellent finish, but uglier than a mud fence.