frame spacing effect on powdered sugar treatment?

[B. Haning]

Do all the frames in each hive body need to have the same frame spacing for the mites to fall through to the screen bottom? I have dusted my hives twice in the past 2 weeks. I am not seeing very many mites fall. I did not do any pretreatment mite counts so maybe there aren't many normally falling. My hives are all in mediums, and the lower one to two bodies have no bees just stored pollen and empty combs. Some of the bodies have ten frames and some have nine frames. Do I need to reorganize these hives to have all the frames line up vertically and take off the empty combs beneath the cluster so the bees are right over the screened floor?

[Jim Fischer]

Why do you have 9-frame brood boxes at all?

[Michael Bush]

Actually you aren't trying to make all the powdered sugar fall straight to the bottom. It's better if it hits a lot of things including bees on the way down. I see no advantage one way or the other on the frames lining up. The bees will try to remove it either way and it will fall and they will groom it off...

[Jim Fischer]

Actually, if you are merely dumping sugar on the top bars and brushing
it between the frames with a bee brush, as advocated by Mr Dowda of
Florida, and echoed by others, you are using a methodology with unknown
efficacy, one untestedy any sort of controlled study.

The approach that was tested and found to control varroa was the
more labor-intensive approach of removing each brood frame, and
"poofing" the bees on each side with a fine cloud of powered sugar
dust, so as to create a maximum number of the tiny (5 to 15 microns)
particles that will clog varroa tarsal pads, and make them fall.

Will dumping work? Mite. Mite not.

The dumping of powdered sugar on top bars and brushing it around is
completely untested by anyone as a long-term control for varroa
with things like controls, so it is unknown if this approach is sufficient.
It seems clear that the bulk of the powered sugar will do nothing but
become hive trash or a contaminant for honey. Certainly some mites
should fall as a result of this approach, but I can show you what
might appear to be an impressive mite fall using nothing more than
water in a sprayer bottle.

So, if you are sugar dusting properly, per the developer of the
technique, your frame configuration does not matter. If you are
sugar dusting in this alternative way, you are not assured of
results by anyone except the beekeepers who have embraced
speed at the expense of predictable results, perhaps useful
results.

[B. Haning]

Why are some spaced nine and some spaced ten? Because some of them were honey supers that the bees moved up into and used as brood chambers. Others were drawn out with the intent to remove a frame and space them as nine, but I never got around to it. I never worried about if a hive body was spaced nine or ten until I started thinking about powdered sugar falling from one bee space straight to the next. If each comb has to be removed and dusted one side at a time I don't think I have time to treat these hives with powdered sugar. I might need to try thymol instead.