Need for oxalic treatment?

[B+.]

Seeley has data showing something like 37% of drones were reared in a different hive to the one they were found in.

Workers is something like 10-45%.

All based on microsatellite analysis.

Interesting, but, we can't assume they carried mites.
I'm working from real observations in my test colonies (https://www.beekeepingforum.co.uk/showpost.php?p=612073&postcount=21854). If I moved the colonies with higher mite counts away, my apiary-level infestation would drop even lower than the 0.11mites/g (1.1 mites/10g) I quoted.
My point is: studies are a good guide, but, we should work from real observations. If they support a different course of action, we shouldn't feel compelled to follow recommendations that don't apply to the situation we face.

 

[Erichalfbee]

Hmm - our association feral beekeeper has hives dotted around Ceredig's country - I thought they were more down Cenarth way though

Emyr. I know who this beekeeper is. He is a honey farmer of sorts. He is as entitled to use fields belonging to unsuspecting off-comers wishing to save the bee as anybody else. I’m really really getting p****d off though. I want to go round my neighbours and do a little persuading.

 

[Beefriendly]

Interesting, but, we can't assume they carried mites.

They don't to any great extent, as I already mentioned.
https://link.springer.com/article/10.1007/BF01218569

 

[Beefriendly]

I can tell you there are lots here.
Here is one instance.

Interesting and also FatShark, thanks.
I must be quite fortunate in nearest managed colonies are at least 2 bee miles distant, and similar for known feral colonies. Hence puzzlement, but seems many are surrounded by abandoned hives.