Why We Saw the Pith out of Hardwoods

Pith in hardwood logs introduces defects into boards, so it is usually sawn out of the lumber. December 6, 2012

I saw mostly oak and hickory for my own use with a WoodMizer LT15. When I quarter saw or rift saw I usually rip boards from the center out. In other words, an 18" diameter tree will provide 9" wide boards or smaller. I have read that the center of the log is oldest and might have defects so that's why it becomes an edge. But I also notice if I see fence posts, deck boards, or larger landscape timbers at the home center they are frequently from the center part of the tree. When do I use the center and when do I not?

Forum Responses
(Sawing and Drying Forum)
From contributor Y:
Boxing the heart of SYP or other softwoods when producing pressure treated lumber is very different than trying to saw for grade in hardwoods. I used to include the pith in hardwood boards when I first started sawing and the defects that occurred during and after drying we impressive, to say the least. You might try it and see for yourself. I have seen large boards rip themselves apart.

From contributor X:
The only occasion where I keep hardwood pith is in some turning blanks, but then I only do it for large bowl blanks or cookies. Cookies obviously have to have them and aren't a problem once turned and dried, and for the large bowl blanks I keep the pith at the bottom and oriented perpendicular to the rotation of the blank.

I don't sell blanks with pith running parallel with the blank that will be in the finished item. I allow pith on the corners of large pepper mill blanks where they will be turned out. For boards I treat hardwood pith the same as Contributor Y, I saw it out of all my boards. There's no reason to have it and you just invite defects by keeping it.

From contributor B:
I use boards containing the pith center to make pallets for stacking lumber on - just put them aside as you cut them.

From contributor O:
I don't have a market for pallet material, so usually I saw my hardwood for best grade then saw the hearts 4/4 as well. I am not a big operation. I will cull out any obvious junk at this time. Will keep short pieces and sticker them in with the other lumber.

I should mention that my son makes cabinets and other furniture, so short or narrower is not a problem. After kilning , and when he goes to use it any bad bits go in his furnace.