Hello Keith,
 All of what I going to post for you is in the archives but will briefly
explain natural mite drop.

> So what would a high mite drop in 24 hours mean, a lot of mites were >in
your  hives or a lot of mites were just discarded from the hive and >now
there are  fewer in it?

I use the same method my friend Allen Dick uses at times. We slip a white
board in the entrance and come back in 24 hours and count the varroa. Dr.
Marion Ellis, Dr. Delaplane and others have written the figure each  feels
is threshold. Many do not agree on threshold.

Threshold is simply the mite load going into winter at which a hive will not
survive till spring without treating or a mite load so high treatment is a
waste of money.   I have treated whole yards with strips which tested over
threshold only to watch all die over the winter. I have been researching
varroa long before varroa was ever found in the U.S. I have  seen  every
varroa problem researchers talk about first hand except coumaphos resistance
yet.

 I tested for varroa by natural mite fall this spring and did not use one
strip this spring. I will do the same in August and if levels are low enough
I won't treat again this fall.

keith wrote:
 A 24 hour mite drop, to me, does not tell how many mites are
> inside the hive, It only tells me how many mites are no longer in the
hive.  This is my opinion, but what do I know?

Dr. Marion Ellis prefers the rolls. I prefer the natural mite drop as less
labor is involved in my opinion. Sorry  to bring my friend Dr. Ellis into
the issue but he is a respected varroa researcher and I have sit through
three of his talks in the last 6 months  (Savannah  "January", Keokuk
"March"  and K.C   "May").
Both tests work if done correctly in my opinion.  Many beekeepers do not do
the rolls correctly by taking bees from the entrance (Marion tests
correctly). The bees need to come from a brood comb to be accurate which
means opening each hive and pulling a frame.  Beekeepers doing rolls get the
results right away. I get my results the next day and invest a second trip
to the hives. I test every hive in the yard and not on a sample few. Why? To
find chemical resistant varroa. Using my method in spring is hard as mite
levels are low then  and testing has do be done at exactly the right time to
be accurate with natural mite fall.

Sincerely,
Bob Harrison


. Dr. Marion Ellis is holding the Master Beekeeping workshops in Nebraska
next week. I will send contact information if you email me directly. I was
told last night there still are a few openings. The three day course is not
easy but you can obtain a master beekeeper certification if you complete all
the requirements. Some do and  some don't. Every beekeeper will learn a few
things about beekeeping he/she  did not already know I assure you.