I am having some mold problems on roundwood timber I am hoping you might be able to help with.
Building is an octagonal structure, using roundwood timbers for the posts, beams, and rafters. We are located in the maritime Pacific Northwest. When I initially cut down the trees for this project, it was late spring. Soon after cutting them down, I used a draw knife to strip the bark, then left them in a part sun-part shade area to dry out sitting on some alder logs (as stickers). They were not rained on. In late summer we started seeing some black moldy growth on many of the logs (again... no rain). We washed all the logs with soap & water. They continued to get moldy. We tried treating them with white vinegar/water mixture & it did not seem to help. The only timbers that did not mold were ones where I stripped the bark later (brutal process where the bark & underlying wood had fused strongly together making the draw knife work very, very difficult; wood after stripping is very dry). The timbers that did mold were the ones that I stripped right away (draw knife more easily gets under the bark, exposing a very slick wood surface). Wood is doug fir & hemlock.
Any ideas on what I can do to prevent this from happening in the first place?
Any ideas on how best to 'treat' the ones that did mold?
Thanks in advance for your time & help. Much appreciated.
To love. To be loved. To never forget your own insignificance. To never get used to the unspeakable violence and the vulgar disparity of life around you. To seek joy in the saddest places. To pursue beauty to its lair. To never simplify what is complicated or complicate what is simple. To respect strength, never power. Above all, to watch. To try and understand. To never look away. And never, never to forget.
~ Arundhati Roy
Spring is when there is the most sugary sap flowing up from the roots, so cutting trees then starts off with the worst possible conditions for mold. The best time for cutting trees for most any use I know of is late fall or winter, when the sap is all down in the roots. Debarking then, or possibly as soon as spring thaw hits (I don't know if waiting that long is detrimental), would get the cleanest job, not as easy as sap-filled wood, but you have seen the results of harvesting sap-filled wood.
My thought is to not worry about it. I think you'll notice that soon slugs will start arriving to eat the mold. Presumably there's other things that will eat it too. Worst case scenario, when you're ready to use the timbers, give them a good sanding to remove the outer layer with the mold.
Hi Brian, that's pretty typical. It'll go away as the wood cures. Are you taking moisture readings? We had a bunch of fresh cut go green and fuzzy and all the neighbors said it was ruined and when it happened to them they threw it in the firewood pile. A year later it is beautiful silvery grey and a joy to work with. Patience, it stays pretty wet here but I've seen some old barns around here that are still standing from Homesteaders.