Harry Goudie suggests shaking bees from a hive in the spring into another
hive and then treating just the bees with Apistan/Bavarol.  If a beekeeper
has properly treated Varroa in the fall I see no reason to treat the colony
in the spring unless, A) you live in the southern US where brood rearing
(and Varroa rearing) occurs most of the winter, or B) the Varroa in your
colonies have built up a tolerance for the chemical.  However, his idea has
some merit for treating swarms when they are first introduced to a hive, or
if a beekeeper wants to make splits with bees only.  This might be desirable
if you have a strong hive on the verge of swarming in the spring.

Then Harry says: "It might be possible to increase the number of strips per
hive."   Ted Fisher is right when he says this use would be contrary to the
label.  EPA regulations do not allow the use of a higher dosage of any
chemical than that specified on the label.  You may however use less than
the recommended dosage (less than one strip per five combs of bees) on the
label, but I do not recommend this action because of the potential for
hastening resistance on the part of Varroa.  Always use one strip per five
deep Langstroth combs covered with bees, or equivalent in other equipment
sizes.

If you want to treat a swarm, neuc without brood, or even a colony with a
high number of Varroa (>100 per colony) in March, you must treat them using
one Apistan strip for each five combs covered with bees, but you can treat
them for less than the label time period (42-56 days).  (Our pesticide
regulators have confirmed that this use is in compliance with the label.)
Leave the strips in the colonies for 10 days, then remove the strips and put
your honey supers on if the colonies need them.  We usually put our first
supers on by March 15 if the colonies wintered as well as they should.

I have treated colonies with high numbers of Varroa using sticky boards with
screens in the fall (Sept.) for two days, then replaced the sticky boards
three times on two day intervals.  My experience indicates that most of the
mites on bees drop within the first five to ten days.  (Of, course there are
still many mites in the brood.)

The label does allow the reuse of strips that have been used for survey
purposes.  I asked and received this information from the manufacturer.
They said that the strips could be reused but they wouldn't use them for
more than a total of 20 days because they didn't know what percent of the
chemical the bees removed per day over time, or if the removal occurred more
heavily at the beginning of the treatment period.  The company expressed
concern about the variability in colony size and ambient temperature.  So
Harry's thought that "the strips could be re-used for numerous hives using
this method" would be contrary to the label.  Some colonies "track" or put
wax or propolis on the strips.  This covers up the chemical reducing the
amount of available chemical.  I certainly wouldn't reuse such strips.

James C. Bach
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