Roe Valley Beekeepers Association
This section covers the current treatments available to local beekeepers for the common bee diseases and infestations.
Control of Varroa, Nosema, Acarine and Dysentry in Overwintering bees
from information provided by Arthur Rainey
None of these treatments should be used before final removal of honey from hives.
Treatments for Varroa
Impregnated plastic strips which kill large proportions of mites on bees but not in sealed brood so they are inserted between the frames when there is little or no brood (eg Late October/ November. They should be kept in place for 6 weeks but no longer otherwise resistance will be encouraged. Apistan is based on hard chemicals (fluvinate) but is probably the most effective treatment known at present
A thymol based gel which is placed in the hive. Limited to 2 applications of 1 tray at 2 week intervals. This can be used anytime except during a honey flow.
An organic treatment newly introduced to Britain this year (2010) and its efficacy is therfore not proven. It is based on organic oils. The makers literature indicates around 90% kill in the 12 countries in which it is in use. The climate in these countries may be warmer with different evaporation/ distribution characteristics.
An organic acid present in Rhubarb leaves and tea. It can be used by trickle or vapourisation and was the subject of considerable discussion in the club last year. The Trickle method involves mixing the oxalic acid with sugar solution and the mixture being trickled between the brood frames onto the bees, whose behaviour will result in distribution. Vaporisation is achieved by placing Oxalic acid crystals on a custom heating tray into the bottom of the hive which is sealed. The vapour is released from the tray and locked into the hive for a defined time. Care needs to be taken with the dose and timing, and the vapour is also toxic causing respiratory damage. Oxalic acid vapour is also effective against acarine and will eliminate wax moths from the hive.
These acids have also been applied by beekeepers using vaporisation mats, but are less popular, and potentially dangerous.
Treatment for Nosema Apis and Nosema Ceraena
this treatment is no longer available in UK
Treatment of Dysentry
Dysentry is a diarroeal illness occuring principlly in cold months associated with unripened stores and stressed bees. Prevention is best and can be acheived by removing crystallised and unripe honey from the brood box and feeding a sugar solution treated with thymol solution, a product derived from thyme.
If disease occurs in milder weather the colony should be transferred to a clean hive and fed heavily.
Treatment of Acarine.
This parasitic mite invades the trachea and is sensitive to the treatments used for Varroa.