Spalting refers to the visual patterns created when fungi colonize dead or dying wood. The fungi leave behind dark boundary lines, known as zone lines, and varying shades of bleached or pigmented wood. Woodworkers prize spalted lumber for its unique decorative appearance, though the fungal decay also makes the material softer and more difficult to machine cleanly.
Heard on the job
That spalted maple bowl has incredible black lines running through the grain.
Insider tip
Because spalted wood is partially decayed, it often requires stabilizing with resins or thin cyanoacrylate glue before turning on a lathe.