In message <v01520d01af13b991dea7@[199.240.82.114]>, Ed Levi
<[log in to unmask]> writes
>There are ways of getting pretty accurate guesstimates of varroa
>infestation levels without using chemicals:  Natural drop on sticky boards
>would be one way.   I beleive, ether roll as a percentage of colony
>population times 5 (for 20% being exposed) would be more accurate.
>Thirdly, I'm sure you could accertain fair comparative measurements from
>trapping (using consistant aged drone brood as the trap).
 
This later one sounds interesting, I'll have to think about it.
The difficulty with using the other two (its obvious with hindsight) is
that you can't simply multiply by 5 (or whatever). The factor varies
with the amount of brood and so when the measurement is taken. Its not
insumountable, just more tricky. Sometimes you measure no natural mite
fall and its not because there are no mites but because the b*****s are
breeding in the brood cells and not falling off!
 
--
Dave Black
<http://www.guildford.ac.uk/beehive>,
Guildford, GU1 4RN.  UK.