John you don't know if you never ask.
Spalting is caused by the infections of wood with various kinds of white rot fungi. The ideal conditions for spalting to take place are temperatures that range from 70 to 90 degrees Fahrenheit with a moisture content that is at or near the fiber saturation point of about 30%. The characteristic blue-black zone lines of spalted wood form when incompatible colonies offungi come into contact with each other and lay down barriers to separate their territories. This phenomenon represents the early stages of the decay process. This incipient decay may or may not seriously weaken the wood, although a gradual softening of the wood is apparent and accompanied by a gradual change in color to grayish white.In the later stages the infected wood is of a dirty white color and becomes soft and spongy.