KTSmith
Branched out member
- Location
- Maine, New Hampshire
Two points:
1. The path of least resistance for electrical current in wood is a function of the concentration of dissolved mobile ions in aqueous solution. Pure water is an electrical insulator, not a conductor. Pure, clean wood is also not a good conductor. Electrical conduction follows the presence of mobile ions. So tissues such as the vascular cambium (and maybe the phloem) and pre-existing columns of wound-initiated discoloration (WID, "mineral streak" enriched in mobile potassium and other electrolytes) are usually wetter as well than the "regular" wood and bark. So the flowpath may well not be a geometrical straight line, but does follow the mineral concentrations. For wooden ladders, wood with mineral streak is not used due to the extra risk of electrical conduction if in contact with an electrical source.
2. Although more recent info on frost cracks might be helpful, I'd start with Heinz Butin's work with Alex Shigo linked here.
1. The path of least resistance for electrical current in wood is a function of the concentration of dissolved mobile ions in aqueous solution. Pure water is an electrical insulator, not a conductor. Pure, clean wood is also not a good conductor. Electrical conduction follows the presence of mobile ions. So tissues such as the vascular cambium (and maybe the phloem) and pre-existing columns of wound-initiated discoloration (WID, "mineral streak" enriched in mobile potassium and other electrolytes) are usually wetter as well than the "regular" wood and bark. So the flowpath may well not be a geometrical straight line, but does follow the mineral concentrations. For wooden ladders, wood with mineral streak is not used due to the extra risk of electrical conduction if in contact with an electrical source.
2. Although more recent info on frost cracks might be helpful, I'd start with Heinz Butin's work with Alex Shigo linked here.
