Spalting Maple - The Horse Poo Experiment

In recent months Kevin has made considerable effort to purchase some figured wood that is commonly known as Spalted Maple.

Given the difficulty he has had finding quality examples of this wood, he has started to explore ways of spalting his own Maple.




What is Spalting?

When most woodworkers refer to spalting, they are usually describing the introduction of dramatic color or black into specific grain lines of wood. This is sometimes produced by mold growth in live or cut wood, or various types of wood disease or rot. Spalting can include myriad forms and colors, depending on the wood, the cause, the chemical elements introduced, etc.

When different types of mold of fungi are present in a piece of wood, black lines are often formed as an interaction zone where different fungi have erected barriers to protect their resources.

Somewhere along the way Kevin found a do-it-yourself recipe that claims that Maple can be spalted by smearing yogurt over chunks of the wood. The wood is then wrapped in plastic and buryed it in the ground for 2 months. Kevin gathered up a variety of 6/4 Maple scraps from around the shop and used them to conduct his experiment.

While it makes sense that the bacteria naturally found in yogurt should have the ability to spalt Maple, I question whether kiln dried solids are wet enough for the spalting process to work. Given that he buried the wood in early June, we'll find out in a couple of weeks time how well the experiment worked.

In the meantime some relatives ended up cutting down a small Maple tree at their cottage recently, and they asked whether I'd be interested in the logs. I saw this as a perfect opportunity to explore a different theory of spalting.

For this experiment I used a recipe found online at a site called WoodCentral. It calls for a mixture of 3 parts dried leaves, 1 part water, 2 scoops Miracle-Gro, 1 part fresh horse manure, and 1 bottle of beer (in this case an Upper Canada Dark Ale).




The photo above shows the ingredients ready for mixing. The dried leaves are already in the pail with the water.




The brew is stirred and ready.




To better expose the wet ends of the logs it was necessary to cut 3" off each end. My father came by with his chainsaw to do the deed. For a 79-year-old he continues to be quite limber and adept with handling tools.




Applying the "poo brew" to the ends of the logs.




The remaining mixture of manure and leaves was placed on top of the bark.




The logs were then wrapped and sealed in plastic, where they'll remain in the Sun for about 2 months. The skid below keeps them elevated, so ground rot doesn't set in.

Check back in 2 months time to see what happened.