Oxalic Acid Vaporiser Treatment on September 20th

After the high count in Aqua from the drone trap last week – 50:100 and the Defra advisory on incidences of high Varroa infestations I decided to use my new vaporiser and apply Oxalic Acid to the home apiary colonies. Will do the Mole Valley ones next week.

Oxalic Acid Vaporiser - completed

Bit of a faff removing the entrance blocks especially as it was the middle of the day and as the weather has continued to be warm the bees were very active. Didn’t see the vapour coming out of the top of the hives but certainly seems effective based on the drop counts. Very easy to use and found the on/off switch to be useful, also liked the fact the battery is relatively light weight so easy to move around the apiary.

Put in Varroa slides before applying the treatment and the 24 hour drop counts were shocking:

  • Aqua – 132 – surprised at how high as this the colony that I have been very focused on drone trapping during the season
  • Blue – 212 mites, might be down to the poor start it got during the season
  • Cyan – 180 mites – very active so after the other results not too surprising
  • Denim – 37 mites, surprised how low it was compared to the others; hopefully the treatment was applied correctly This has been a very active colony throughout the season
  • Honeydew – over 300 mites. Very surprised as this was a new colony this year but I obviously haven’t been managing it for Varroa very effectively. I thought the it would be one of the lowest as it was set-up as a nuc and I didn’t use drone trapping.

Second count 48 hours after treatment not much better (either the treatment is really effective or my colonies are in a very bad state!):

  • Aqua – 85 mites
  • Blue -180
  • Cyan – 60
  • Denim – 10
  • Honeydew – 260

With such high counts I will treat again in 3 weeks. This is one of the advantages of using the Vaporiser is that the treatment can be repeated.