I find it interesting that all who talk about Oxalic Acid treatments
refer to some how putting it one the combs in some sort of a solution.
The method I was made aware of is to use a crystal form and to vaporize
it into the hive from the entrance.  The treatment would last 3 minutes
and then the entrance would be sealed off for 10 minutes.  This type of
treatment would supposedly cost $0.05 a hive.  They are boasting a "up to
99% effectiveness" with 5.0G of Oxalic Acid.
Here is the link to look at this info
http://www.members.shaw.ca/orioleln.  I was told by the manufacturer that
Oxilic Acid is not registered in the US for varora treatment.  But they
did mention that they have many customers in the US.  For what I would be
interested in knowing.  Is anyone familiar with this method?
Garrett Martin