What is that on this board. It was to high to reach in the attic.
Gary,
I’ve only seen this a few times, not much PTW used in attics around here, but the old CCA treated wood along with heat, moisture and age patinas forming that bluish staining…the climate down there would be prefect for this
This was an inventory home built in 2007.
Why didn’t you say that in the first place, instead of wasting all my precious time? 
:mrgreen:
Now I haven’t got a clue, any better photo?
Gary,
What happened to your flash?
I can’t see a damn thing.
It was so far up there and at an angle.
can’t see it.
Looks like a piece of soffit baffle to me .
I bet there is a roof vent above and they did not want it open to a rafter.
…Cookie
It may also be a piece of Blu Wood, almost forgot about this because I don’t see much of it around here.
I’m just guessing, because like the others, I can’t see it very well in the picture. But could it be dirt/debris? I see quite a bit of “dirty” wood in various locations. The wood gets in the mud or rained on, or whatever prior to construction and is then used anyway without being wiped off. I saw one house that had muddy footprints on the underside of the subfloor. It looked like someone walked across the basement ceiling. I always ask myself, especially in situations like this where I can’t get to it very well, “is it just the one piece of lumber?” If it’s all over, or in other places or even on adjacent pieces of lumber, it may be more likely to be more than just dirt.
Hope that helps