How do you air dry a Black Walnut log for use? Is it better to have it cut into lumber, then dry the lumber? Or is it better to dry the log, then have it cut? It seems from what I have been reading it's done both ways?
I want to use the wood from a back yard Black Walnut tree grown in SC. Someone told me the wood would have more humidity than those from the north. How will that affect how it is best to dry the wood?
I appreciate any help with this.
It will develop many stress cracks dried as a log. It will also take several years. Or many months in a kiln. The moisture from north to south will be minor if any.
If you cut it into lumber it's going to need to be planed after drying to glue it back together. Hard to tell how much planing will be needed.
You will get much better quality lumber if you saw the log and dry the boards. If you dry the log first, it will split and crack very badly, and the lumber quality will suffer greatly.
I also strongly encourage you to saw lumber as soon as possible. This will qlso help with insect control.
A backyard tree is likely to have tramp metal that can damage a sawblade, so might cost more. Use a metal detector to find most iron metal.
Due to root damage in a backyard tree, it is common to find a bacterial infection that can change the wood color, will weaken the wood making cracking more likely, will increase the initial moisture in the wood, and will give the wood an unpleasant odor. It does not affect all pieces of lumber and is often restricted to the lower end of the log closest to the ground. Upper logs seldom have an issue. Be alert and plan to eliminate such wood when you are sawing, if possible.
An add: Air dried black walnut is preferable to work with in lieu of kiln dried (cuts and carves much better). I have air-dried 10's of thousands of BF of it, and it's the only way I like it for woodworking. In my area, any bug issues are in the sapwood and not the heartwood.
This will help a lot. Thank you.
I'm curious where you read to dry the log before cutting into lumber. I've never seen that as a recommendation since any log will fill with bugs and severe checking in log form.
Well the tree service was able to come lay the black walnut down before Irma hit Florida! I was so relieved, especially since at one point they thought SC would get harder hit! After the storm they came, cleaned up the branches, and I had them grind the stump. (That messed up the back yard with tracks.) There was no infection or metal.
A week later someone with a portable sawmill came and rough cut lumber from two lower logs. He cut it so that it could be planed nicely. He estimated it was 75 bf. That was very hard work! I was glad to find someone to do it.
He showed me how to re-stack the lumber in my shed. I decided to make a bace off the ground with a metal grate on cement blocks, then stack it like he showed me beginning with the stacker wood pieces used to separate the layers. What else needs to be done to dry the wood nicely? Does it need moved every so often, or not. How long should I let it dry before further evaluating exactly what I have?
For what can the sawdust be used? Would it help my yard where the walnut was to mix it with the dirt around there? I'm wondering how to level the ground again too.
I was looking on the internet for how to dry wood. I don't know the exact place where I saw something about drying wood as a log. I figured I could get better and more knowledgeable information here on how to do things with wood!
Thank you for all the comments. They have really helped!
The wood should dry nicely as long as there is good air flow and the stack is protected from the elements. It will take about 3 or 4 months for the wood to air dry if it was cut 1" thick. You did not say how thick the boards were cut. 2" lumber takes over twice as long to air dry as 1" lumber. You do not need to move or re-stack the boards. If there is not good air flow, then you can use a box fan to create air flow. The air moves the evaporating moisture away from the wood.
Make sure that your foundation with the blocks and grate is level and flat. The wood will take on the shape of the foundation, so a flat foundation equals flat lumber, which is the objective.
Walnut sawdust is not a good mulch or soil amendment. It can contain a chemical called juglone that kill other plants. I would not mix it in your soil.
Just to add: walnut saw dust is also toxic for animals, so not suitable for bedding, etc.
I burn or bury my walnut sawdust.
Good luck!
Professorial ramblings: Allelopathy is a biological phenomenon by which an organism (walnut tree, in this case) produces one or more biochemicals (hydrojugalone, which converts to jugalone, which is quickly oxidized into other allelopathic chemicals) that influence the germination, growth, survival, and reproduction of other organisms. The allelopathic effect of walnut trees, roots, leaves, etc. (as a herbicide for some plants like tomatos, but not for many grasses and other plants) has been know for around 2000 years.
Dr Gene,
I've heard old-timers allege that walnut causes lung issues (cancer) etc.
Any scientific precedent to this?
Thx
Thank you for the information on drying the wood and allelopathy. That will help a lot. Would the walnut sawdust help deter growth or kill nutgrass? We have a place which I don't want much to grow between two fences. Would the walnut sawdust help wild grasses and weeds not to grow there?
Yes, if it is 3 or 4 inches thick.
I suggest putting a flat tin cover over the pile to keep rain and direct sun off the top boards. But keep sides open for breeze
Ok I'm trying a post, and will post pictures when I can. I just measured the walnut lumber last week, and was wondering if there is a way to tell about lumber grades from pictures. It looks like someone is willing to get the lumber to use!
Most hardwood lumber is graded using the standard rules. However, walnut is usually graded using a different set of rules and techniques, as often the final pieces are quite short. It is not easy to find a grader that can do walnut accurately.
Grasses aren't much affected by walnut as they've adapted. Other plants can't tolerate it. Just burn the dust if you have a burn barrel or fire pit.
Hopefully you don't think you're going to get rich selling 75 BF of walnut lumber? Good grade 1x might be worth $4/BF if it dries straight in my opinion. But you're not a regular seller with a shop, so someone on Craigslist will probably try to get it for less. Slabs might be worth more. Is that your intent or are you going to use it? I'm sure the Sawyer wasn't cheap. Keep in mind that outside it will only air dry down to 12-15%. For furniture use, it's need to be down to 8%. You need to kiln dry it once it air dried to get down to that. Another option is to bring it into a conditioned space (stickered) for a few months where the humidity is far lower than outside.