Managing Fungus on Cedar

Advice on handling and cleaning a Cedar slab that wasn't properly dried and now harbors fungus. October 19, 2014

Dr. Wengert and other contributors: The April 20, 2011 posting, "Managing Mold While Drying Cookies With Pentacryl" has been read. A customer recently returned a 3.5" x 25" incense cedar slab to us for surfacing. We green cut in the slab during the fall of 2012, and it was placed on cedar supports by a contractor shortly thereafter. The contractor was advised to remove the slab and place it in a dry environment during the winter months to aid air drying. Instead the contractor applied a commercial sealer to the top and ends, not the bottom, and left it outside during the winter. A white fungus developed where the cedar supports contacted the slab. Slab moisture content is aproximately 13% near the outside edges and above the meters capability near the center. It actually feels wet to the touch. We would like to treat the mold condition prior to placing the slab in our solar kiln to reduce the possibility of introducing the fungus to the kiln. Please give recommendations regarding an appropriate home remedy and/or commercial treatment solutions for use after as much dry mold as possible is mechanically removed.

Forum Responses
(Sawing and Drying Forum)
From contributor W:
I am not sure if my experience applies here but we see a lot of standing dead cedar logs end up at a shingle and fencing mills. They usually come from places flooded during road construction but they create a big white fungus problem. Be sure you wash down everything that might have any of that spore around. Once people live through that one time, they get very fussy about what is coming into the yard. It is never a problem with trees cut when alive. But you had the hunk of wood around a while so maybe the wood though it was long dead and welcomed the fungus aboard.

From the original questioner:
There does appear to be similarities between what takes place with standing dead cedar in your area and what happened with the slab we cut. Are you aware of any home mixed solution or commercial chemical that may be used to treat the fungus that is local to your area?

From contributor W:
Some people tell me they spray once a week with a 6:1 solution of water and bleach. There is probably some EPA rule about that so check that out. They use a one gallon garden sprayer. These days you have to be careful about recommending any chemicals to anyone for any purpose so I am just reporting what people tell me.

From the original questioner:
I understand that the information in your response is only a reporting of what others have indicated to you. My only concern about using a 6:1 water to bleach solution is the possibility of bleaching out some of the deep red color. The fungus growth was on the bottom of the slab; however, there are some deep cracks on the bottom surface. I do intend to fill the cracks with a special epoxy/sanding dust mix once the moisture content stabilizes. So far the fungus does not appear to be redeveloping. The first warm sunny day I will move the slab outside, wire brush the residue, vacuum, and apply one or more bleach solution treatments. From there it will be on to the kiln.