Bruce, I found more info on the heat treated wood.
It appears as a new technology from Canada.
I grabbed an exerpt here and there and put it all together, for I was on a lot of different sites and suppliers.
Heat Treated Lumber
WWPA offers a heat treatment certification program for mills to stamp qualifying lumber with the KD - HT mark.
This service is intended to assist mills in supplying products that meet the standards for wood packaging
materials that may be exported.
Wood Packaging Material (WPM)
Wood packaging material made of unprocessed raw wood is recognized as a pathway for the introduction and spread of pests. To limit the entry and spread of quarantine pest through international trade, the International Plant Protection Convention adopted the International Standards for Phytosanitary Measures Guidelines for Regulating Wood Packaging Material in International Trade (ISPM 15).
Termawood is an unique technology that uses heat treatment for timber processing to significantly improve various characteristics of wood.
Termawood vapor-stabilization technology is a patented wood heat treatment technology, utilizing a natural thermochemical reaction and steam at temperatures of 230-240 C without ANY chemical additives.
The molecular changes in wood composition result in unique features:
• Water-repelling at a molecular level
• Dimension stability improves 12-17 times compared to untreated wood
• Resistance to biological decay is 15-25 times higher then of untreated wood
WestWood Heat Treated Lumber Production Corporation is unique technology that uses heat treatment instead of chemicals for timber processing to significantly improve various characteristics of wood. WestWood Heat Treated Lumber Production Corporation vapor-stabilization technology is a patented wood heat treatment technology, utilizing a natural thermochemical reaction and steam at temperatures of 230-240 C (450 F) and exclusive of any chemical additives. The molecular changes in wood composition have a result of dimensional stabilization, protection against rot and wither, and as a result, expanded use opportunities.
Hope this helps a bit. :)