Jean Pierre wrote:

> I will experiment the screened bottoms next summer. I was planning to try
> using tobacco smoke in my smoker to artificially provocate the mite fall. In
> Ontario tobacco smoke has been used in conjunction with a sticky board as a
> sampling method. This method has been discarted because it was not sensitive
> enough to show early infestations. Nevertheless I think tobacco could be of
> some help. Has anybody used tobacco smoke aganist varroa? What is the best
> type of tobacco for this purpose?

I have used tobacco smoke, on nasty hives, for several years.  I save the
mean hives till last and put a small amount of leaf in the smoker before
opening the hive.  I purchased a grocery bag of culled cured tobacco leaf
from another beekeeper who has contacts in southern Ontario. Late last July,
I noticed damaged bees(little or no wings) in several hives.  I put sticky
boards on the hive bottom boards then smoked the top bars heavily and closed
the hive. 4 hours later the sticky boards were removed revealing hundreds of
Varroa mites in several hives. These were treated with Apistan after the
honey supers were removed and most survived.  Several hives that didn't show
as many mites were treated with Apistan later in August but died in the
fall. Bees don't like tobacco smoke and its hard on the beekeeper if you get
downwind of the smoker but it seems to knock Varroa for a loop.  Whether it
is effective as a treatment or just as a quick test I can't say.  A closer
look at all of the sticky boards or another test in a week or two might have
saved the other hives.

Bob Darrell
Caledon Ontario
Canada
80W 44N