I am going to provide my opinion for what its worth. I believe I see what is
causing the winterkill from this post and would like to add my input.

> In Western Canada, beekeepers use strips once a year, either spring or
> fall.

Most U.S. commercial beeks dropped this practice when strips began to fail.
For years we only used one apistan strip a hive and had a 98% kill. The
maker would love to have sold us four strips to place in out doubles.
However through careful testing we found one strip worked fine. However
after 5-6 years the scenario with apistan changed.

One study done at the U. of Georgia reported a 2% kill and the infestation
of varroa rapidly increased while the apistan strips were in.


At that time when we had KBV formic  was used as a supplement
> treatment to be used in the season when strips are not used.

"when the strips are not used"

Are you saying you rotated yearly with formic?

 If so I believe this is a big problem.

 David vanderdusen has said that a formic treatment will control varroa for
four months ( presentation at the Austin ABF meeting).  David & I sat down
right before David caught a plane home and discussed the issue. I went home
and tested the miteaway two pads and found four months control (in spring
when brood rearing is highest) is about all the control you can count on. I
did have some success with not treating for up to five months when miteaway
2 is used but after five months varroa is in the drivers seat!

So if Canadian beeks are putting patties on in February with say 7-8 months
of brood rearing I see big problems with the scenario going into winter *if*
no fall treatment is done.

  Having said that. If a colony treated with strips
> in the spring and not treated in the fall, the following spring mites will
> be high. Summer season is too short to have a peak in the fall.

I disagree with formic (based on my personal discussion with David
Vanderduesen).  I think we are on the same page but clearing out varroa *if*
loads are high is important regardless of a set plan (such as use this strip
on the 4th of April  or do not treat on the 4th. of April and treat on the
4th of August for those beeks which *do not test*  and only go by what
researchers say to do)  In the U.S. we have many of these type beekeepers.
However most commercial beeks of the mindset are out of business trying to
pay for their adventure into commercial beekeeping.

One needs to test and treat in fall to keep from having a *peak* in spring.
One needs to winter with as low a varroa load as possible to winter better
and also prevent coming out of winter with a high varroa load.

My personal observation is formic is not the best treatment when varroa 
loads
are high. Works poorly. It is also my observation you can get excellent
control with formic if you monitor and treat as needed.

David Vanderdusen said in California where beeks are brooding bees year
around three miteaway 2 treatments might be needed ( Austin ABF
presentations).

Feel free to contact David as I am only repeating what David has told U.S.
beeks.  Because you helped develop Miteaway 2 do you disagree with what
David V. is telling us? If so please correct me as I buy and use miteaway 2
at times.

> Secondly; there is another management difference; beekeepers will start
> feeding bees pollen patties as early as late February. By the time it is
> spring your might level will build up and increase. So, Mite levels will
> respond to how many brood cycles developed during this time.

I agree. Varroa control is all about the math.


> Thirdly, in these case where KBV was found, colonies were not in good
> shape. This means that varroa mite treatment failed.

So my original question is did the hives crash from poor varroa control and
KBV was only the result of poor varroa control?

In other words poor varroa control led to hives over threshold and the PMS
in which KBV was detected ( along with many other virus I suspect).


> The case was studied and investigated by people who have been in the
> apiculture field for long time.

I am one of those people and the young uns keep using the word dinosaur ( at
times Mr. dinosaur).

When I was young I though my Dad was not very smart. I was amazed at his
level of intelligence as I became older.

I recall that many commercial
> beekeepers had good bees. I guess that is life "Bad things take over and
> get more attention".

Many U.S. outfits did not lose bees to CCD.

Thanks for the post Medhat! its wonderful to be able to discuss issues with
a person of your vast beekeeping experience!

All I know about Canada beekeeping i either learned from Allen Dick, from my
Canadian friends posts on BEE-L or from talking to those beeks in the halls
of national meetings.

bob

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