- Sep 23, 2010
- Reaction score
- North London, West Essex and Surrey
- Hive Type
- Number of Hives
Sounds like your late summer and autumn bees were compromised by varroa and the colonies struggled to survive. A January treatment (what was your schedule?) may have helped but if bees were in tight cluster due to cold the OA will not have penetrated the nest and taken effect.Treated rather late with sublimated oxalic acid in January
It's been pretty cold here, so build-up may be delayed.
Do you use a drifty Varrox or the fire-extinguisher Sublimox?