How much varroa drop expected with oxalic acid sublimationn?

[echidna]

In my (limited) experience and understanding, the total number of mites falling is not relevant - it's what they level off at that's important. If you get hundreds of mites initially but the counts level off at 10 per day then you still have a problem according to NBU advice, but if you only got 30 initially and counts level off at 0 or 1 per day, then you probably didn't have many mites to kill in the first place.
I was horrified at my initial falls in my first two years because they added up to far more than the colony should have had according to the NBU. However, I got the counts down to 0 or 1 after multiple vapes and the colonies did then overwinter alright.
If you haven't seen it, the NBU (Beebase) have a leaflet on their website with a graph showing what levels of fall are cause for concern at different times of year. These are for natural fall, so should be used once the counts have levelled off after treatment to see if it has done the job. Obviously there's plenty of room for interpretation with size of colony and level of activity/clustering etc.

 

[polymath]

Yes for that area of Sussex

I live in Surrey, my research has proven the same.

 

[Erichalfbee]

I live in Surrey, my research has proven the same.

Ah. You didn’t say that.
What I meant is what happens in Sussex doesn’t necessarily happen in Yorkshire for example but I can see how it might in Surrey

 

[polymath]

Ah. You didn’t say that.
What I meant is what happens in Sussex doesn’t necessarily happen in Yorkshire for example but I can see how it might in Surrey

Agree, although given the research and mine was done over a number of years, each year the temp was different but the results were similar. Sure when it was colder more had less brood. I have a belief, stress only a view not backed up by research, that it is not temp driven at all but simple daylight, when is the shortest day of the year, Dec 21, so no surprise broodless is around then mid Dec. After that Bees start preparing for summer, to that end it would be interesting to see research from Scotland, Yorkshire and other shall we say colder places up North to see if it mid dec or jan when colder that you most often get broodless periods. My personal believe is it will still be mid Dec but interested on any findings.

 

[Arfermo]

I don't count, I treat. Counting for me is a complete waste of time.

I gave up too as soon as I ran out of fingers. Looksee and you will know if it is bad enough to do something to annoy the occupants of the hive - sublimate or icing sugar?

 

[Hachi]

I gave up too as soon as I ran out of fingers. Looksee and you will know if it is bad enough to do something to annoy the occupants of the hive - sublimate or icing sugar?

Never had much success with sugar rolling so I bought the Provap 220 and run it from a geny from the back of the truck. very fast and quick.