Green Mold Appearing On Birch Live Edge Slabs

[JustMillingAbou]

Recently I milled up a river birch and over the last few days it has started to accumulate green mold spots on it. I have the slabs stored in my garage stickered up and there is no humidity or condensation along with it being in a well ventilated area. 

Any tips or suggestions would be a blessing as I would like to work on this wood.

[Ianab]

More air flow. Set up some fans pointing at the stack to move the moisture away. Once it gets partly dry the mold will stop.

[WLC]

Ianab beat me to it.  Turn a fan on it.  

[GeneWengert-WoodDoc]

From a technical viewpoint, mold is a fungal activity.  To be active, fungi require moisture, food, warm temperatures and oxygen.  Eliminate one of the four to control their growth.  Nothing we can do to eliminate the sugars in the wood near the bark, or oxygen or temperature.  So, our only control, other than poisoning their food supply at the surface BEFORE they become active, is to eliminate moisture...basically under 22% MC at the surface will not support their growth.  Once a fungus gets beyond the surface, it becomes harder to control because we need to eliminate the moisture deeper within the wood.  Or stated another way, it is easier to prevent the initial attack than to prevent or contro damage once they have started.

So, to drythe wood quickly, we need warm temperatures, low humidities and brisk air flow.

Note that 130F will kill existing fungi, but can also cause darkening of the color of wood and maybe weakening so at low RH surface and end checking is more likely.