Term for the markings in this wood

[Jim Laumann]

This is some black walnut from a tree that died several years ago. It has been sitting in the weather, and was going
to be firewood, but now that a lathe lives in my shop, I've been giving it a second look...

I cut some chunks of it up the other day, and found these markings.....I know it's some sort of water/fungal/bacteria reaction, but what is the correct term to describe it? Spalting?

Thanks

Jim


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[Roger Chandler]

That is referred to as "spalting" a much desired trait in wood, as it makes for some striking figure in a turning. Be aware, that spalting is the first step in the decaying process, and you need to make sure your wood blank has integrity to be held securely in a chuck or between centers..........you don't want that piece of wood flying off the lathe and hitting you in the face and sending you to the emergency room for stitches, a lost eye, or worse........wear your faceshield for safety!

looks like those two pieces would make either a nice lidded box or a hollow form........good luck!

[Brian Brown]

Also be aware that spalting is a living fungus, that can cause some respiratory problems. Always wear a mask, or better yet a respirator when turning it.

[Reed Gray]

I would have to put my hands on the first piece, but the lighter spots are most likely rot/punky wood, and will be much softer than the darker wood. It is most likely the sap wood from the tree as the heart wood almost never rots or gets bugs in it. The second piece, the black streaks are spaulting, which as others have said is a fungus, and is a stage in decomposition/rotting. Again, this is some thing I have never seen in the heart wood, only the sap wood. The sap wood does turn more brown as it ages, especially if the tree has been standing dead for a while.

robo hippy

[Barry Elder]

I agree with Reed, and if you can dent the white areas with your fingernail, it is more or less a rot giveaway.

[Jim Laumann]

I will need to check out the white spots for softness - hopefully tonight. I will report back.....

Jim

[Jim Burr]

Thanks for pointing that out Reed...you're my hero for the week!!! You can kill that stuff by freezing it. Assuming it's Ziploc size, toss it in a bag and then the freezer for a week. Shazaam!!! Now the fungus is dead, but the spores are still there and so are the soft spots. Several of us can, depending on the size of the blank, can stabilize it to eliminate the soft tear-out. Never toss out a blank that can be stabilized!! Good looking chunks, should make cool stuff when done!

[Jim Laumann]

Thanks for the all the tips and suggestions....

I laid my fingers on the wood last night - using my thumb nail, I could make a slight dent in the dark wood, and about the same dent in the lighter colored wood. Nothing "mushy" where I could dig out chunks of fibers.

I forgot to indicate the size of the blocks, they are approx 1 3/4 - 2" sq by 5-6" long - was planning on using them for Christmas ornaments.

I always wear a face shield when using a chisel, but have been cheating and not using one when sanding....I 'spect I should be more dilligent in that aspect. The dust mask is a good point, as is the idea of freezing them.


Jim

[Reed Gray]

Some times splotching like that can just be areas that haven't darkened/oxidized yet, like the sap wood is prone to do.

robo hippy