Black streaks in Red Oak?

[Kent Adams]

I was resawing some red oak that has been sitting in my woodpile for 2-3 years (shielded from rain completely). Most of what I've resawed has been really nice, but this red oak had a lot of black streaks in it. The streaks aren't coming from the blade, are not soft or susceptible to smearing. The one thing that made this log different than the others was that the end grain had turned dark, whereas the other's were not dark.

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[Jim Seyfried]

It looks like spalting to me.

[Kent Adams]

It looks like spalting to me.

Is that an ugly form of spalting?

[John Schweikert]

Spalting: fancy word for fungus rot.

But can be attractive nonetheless.

[daryl moses]

Mineral stain. Fairly common in Red Oak.

[Jim Andrew]

The industry considers that poor quality and terms it "black oak".

[Ron Kellison]

I found a great deal on mineral stained red oak a few years ago. It was a brownish streaky stain rather than yours which is black but it made wonderful flooring! Other than the stains it was dead clear and machined well.

[Fred Heenie]

When I see black in red oak my first thought is tannin stain. Any moisture at all and contact with iron will cause a stain. Hinges on an unfinished cabinet wet from rain drops will be a cause as an example. If you can rule out the metal, you can move on to something else. HTH

[Danny Hamsley]

Definitely fungal spalt.

[Dan Hintz]

It tends to follow the growth rings and has very undefined edges... I'd call that mineral stain. Spalt is the opposite... (relatively) nicely defined edges and doesn't necessarily follow growth rings.

[Kent Adams]

The end grain was definitely spalted, I was excited to cut it open, but found the interior stained like this so I think it probably was spalt, but spalt gone bad.