Sealing Spalted Maple Log?

[Al Weber]

I had a soft maple fall in a recent windstorm and when I began to buck it up to move it out of my access road, I found a lot of spalting in it. I salvaged 3 logs ranging in length from 6' to 10', roughly 12" diameter at the butt end. I coated the ends with Anchor Seal but then got to thinking maybe that wasn't a good idea as the maybe the spalting will continue. Right now, probably 20-25% of the cross sections show spalting. Obviously I can cut a couple of inches off each end if sealing them is not the thing to do. How best to handle these? I think the tree has been dead for 1-2 years if that is of any help.

I know these logs won't yield much spalted lumber but I use it in door panels and jewelry box tops and sides so small pieces suffice for my needs.

 

[woodshop]

I had a soft maple fall in a recent windstorm and when I began to buck it up to move it out of my access road, I found a lot of spalting in it. I salvaged 3 logs ranging in length from 6' to 10', roughly 12" diameter at the butt end. I coated the ends with Anchor Seal but then got to thinking maybe that wasn't a good idea as the maybe the spalting will continue. Right now, probably 20-25% of the cross sections show spalting. Obviously I can cut a couple of inches off each end if sealing them is not the thing to do. How best to handle these? I think the tree has been dead for 1-2 years if that is of any help.

I know these logs won't yield much spalted lumber but I use it in door panels and jewelry box tops and sides so small pieces suffice for my needs.

Alhtough some would dissagree on here, I've found from experience that most species, even if they've been dead for several years retain most of their moisture, spalted or not, until they are milled into boards where they can dry. They will lose SOME moisture just sitting there in log form, but again, with most species not a lot. Thus if you don't seal the ends, they will start to crack.

 

[Zodiac45]

I agree with Woodshop,

Regarding spalted wood in partiocular. Sealing it on the ends for cracks is about all you can do. The spalting is caused by decay and bacteria in the wood. Sealing it in will possibly accelerate decay. I would treat it like any otherseasoning slab except it might be better too tuck it away and out of direct sunlight.

 

[Brmorgan]

Actually from what I've read, putting it in direct light will probably more or less halt the spalting process. It's caused by various fungi and they seem to prefer a fairly dark, humid, warm environment - I've read about 80% humidity, 80°F. If you want to spalt the entire log, the best I can suggest is to cut it into boards now, and place the boards inside a box with the sawdust you produced, any pieces of the fungi that might be attached to the bark on the log, and maybe a little bit of moist humus from around where the tree was. Then put this box in an environment as described above for a few weeks and the spalting should spread to the whole board. Be sure to check up on them regularly though. There was a whole article in the August 08 Fine Woodworking describing this very process amongst other info on spalted wood, so I'm only relaying the info. I did do something similar a couple years ago with a birch round and a garbage bag to make a couple of spalted bowls on the lathe though. It did spalt some though it wasn't spectacular, but I also didn't put a whole bunch of sawdust etc. into the bag, just the piece of wood.

If you're not going to cut right away, I'd seal 'em up to halt the spalting - if it's left uncontrolled, it can destroy the wood surprisingly fast. White rot can destroy parts of a log's integrity in a matter of a couple months given the right conditions.

 

[Burlhunter13]

I have milled alot of spalted wood, everything from oak, boxelder, maple, elm, hickory, apple, etc.

The worst to work with is maple and boxelder personally.
I air dry (building a kiln this week) my wood. And I have noticed that this wood will mold unbelievably quick, as fast as overnight if left in sluggish air. Best thing to do would be to mix up a concentrated bleech and water mixture. This slows the spalt tremendously! After the boards are milled I rinse them off with a hose to remove any wet sawdust from my bandmill, then I let it air dry for a few minutes. Right before I stack it I mist all sides of the spalted lumber with the bleech mixture from a pump sprayer. let that air dry to touch, then stack it. It makes a world of difference! It still might mold a little near ink lines and such, but no where nearly as bad. Nature of the beast.

Because the logs are kinda small diameter, air drying is going to suck, you will have a lot of warping most likely from the pith being so close...so mill the boards as thick as you can and hopefully they will not crack on the spalt lines like some of my 1" stock did here. If you see any cracks then wax them quickly to prevent them from running. In any case, slow, extra careful drying.

Or you could go the interesting but slow route.
Wax the ends of the logs and let them sit uncovered under shade for another year, you could lift them an inch off the ground if you like. Let the spalting continue...the logs are already spalted....might as well get some nice heavy spalted maple boards!

Cheers!

 

[Zodiac45]

That bleach treatment makes good sense Burl. I've used it on the cedar gutters around my house too remove fungi, etc.. and as a pre treatment before anti mildew undercoat paint.

 

[dallasm1]

I have noticed the speed of mold growth on my milled maple as well. The bleach spray is a great idea. I am cutting maple trunks from 4/4 to 16/4 and about 35" across and air drying them. I noticed the mold (no rain, air dry) after two days. I am going to mix up a batch of bleach right away to spray them down..... Thanks for the info!

 

[Backwood]

sealing the ends I think would be better, I would cover it with black plastic though. wet it down good to when you cover it. Hear some people spraying beer on it to encourage mold.
I have some logs both ways, ( covered and uncovered ) and the covered ones look much much better.

 

[Backwoods]

Keep the bleach away from Redwood, it will turn it black.

 

[Burlhunter13]

sealing the ends I think would be better, I would cover it with black plastic though. wet it down good to when you cover it. Hear some people spraying beer on it to encourage mold.
I have some logs both ways, ( covered and uncovered ) and the covered ones look much much better.

+1
I never though of using beer! Thats a great idea, my neighbor pours his old beer into his compost pile, it speeds up the decay process, I didnt make that connection for logs lol.

Only problem with letting the spalt go too far is that you can get the really really spongy spalt thats hard to mill and work with without destroying it. Covering it with plastic is a good idea as long as you dont forget about it and check once every few months.

Cheers

 

[Al Weber]

Just an update to advise that sealing the ends is the correct thing to do. I had sealed all the large logs with Anchor Seal but left two small diameter logs unsealed because I forgot them until a couple of days later. Both the unsealed logs were splitting on the ends already. I cut them down and sealed them yesterday to try and salvage them although they won't yield much anyway. I'm going to let them lie for awhile and see if the spalting continues. And I'm not pouring my beer on them yet either.

 

[Burlhunter13]

Just an update to advise that sealing the ends is the correct thing to do. I had sealed all the large logs with Anchor Seal but left two small diameter logs unsealed because I forgot them until a couple of days later. Both the unsealed logs were splitting on the ends already. I cut them down and sealed them yesterday to try and salvage them although they won't yield much anyway. I'm going to let them lie for awhile and see if the spalting continues. And I'm not pouring my beer on them yet either.

The logs should be in a darker spot that is moist. Without the water/beer the decay process is going to take forever. I milled trees that have been standing dead (in a field with lots of sunlight) for 7+ years and sometimes the spalt doesn't go beyond 1 inch deep. Covering it in plastic is a good idea.

Cheers!