Borates are Effective!

BoraSol WP treated wood does not affect MOE or MOR strength or integrity of wood and does not corrode steel or galvanized steel fasteners.
 
Borate treated lumber is approved by the American Wood Preservation Association for Use Category level 2 and is accepted or required by most state Residential Building Codes.  
 
Borate treated wood is also effective against cockroaches, silverfish and ants.  One treatment for many insects.

“After 30 months of unprotected exposure to approximately 145 inches of rainfall, sufficient boron remained in DOT treated wood to be toxic to termites…this finding suggests that borates leaching from building timbers during distribution and construction should not greatly deter effectiveness.”*

* - L.Williams, First International Conference on Wood Protection with Diffusable Preservatives.