In 2019 we made a study on efficacy of OAE (Oxalic Acid Extended) long term treatment. We then used strips of absorbing paper used for conserving flowers. We found an effect but in the long run it was not enough to stop the mites build up. Perhaps this was due for bees removing and propolising the strips.
Randy Oliver has presented promising results using Swedish sponges “Wettex” as carriers for the liquid.
Since it is of vital interest to find a remedy that is effective and doesn’t have the drawbacks that other treatments have. (Disturbing the bees, contamination of honey and wax, building resistant mites, expensive, environmental impact etc). We conduct a new study using “wettex”strips.
Is OAG on wettex strips good enough to control varroa?
Treat with 50 g Oxalic Acid in a mixture with Glycerol 1:1 by weight. Distributed on four strips each contains about 12 grams OA. Measure varroa infestation by counting downfall every day for 50 days.
We use five colonies of Buckfast/Elgon strain in the home apiary. Monitoring downfall every 24 hours in the afternoon.
Starting by measuring natural downfall before applying OAG.
As experienced from our other studies effect takes about 24 hours to manifest. Which indeed seems to be the case here as well.
Three of the colonies have low infestation. Nr 3 and especially nr 15 are heavily infested. Which also was clearly indicated by analysing with the BeeScanning app as well as the natural downfall.
To be continued.