Species and wood science
Spalting
Spalting is dark line and colour patterning formed by fungal activity in wood that has started to decay.
What it means#
Spalting appears as black zone lines, grey streaks, or coloured patches created by fungi in partly decayed wood. It is common in maple, beech, birch and other pale hardwoods.
Why buyers care#
The pattern can be valuable, but the same process can leave soft, punky areas. Those zones may crush under tools, drink finish, or need resin, hardener, or removal.
What to check#
Ask for close photos and hardness notes where the spalting is strongest. Check moisture, thickness, and whether soft areas sit near edges, joinery, screw positions, or high-wear parts of the design.
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