With the warmer temperatures now arriving, we are getting many queries about mite treatments and when is the best time. Several have been from new Keeps concerning the use of Oxalic Acid so here is some information on the process. The most important consideration to using Oxalic Vapor is remembering it only has an effect on exposed mites, which means that those mites on brood are not affected.
When should I use Oxalic Acid Vaporization?
There are many variables in this question and certainly a keeps choice. Generally, it gets applied prior to winter, after a swarm has been hived and is producing eggs, with package bees once eggs are observed, during a mite spike and in the source hive of a split. It’s important to note first off that Oxalic Acid in vapor form does not kill mites that are already in brood, so, while a treatment will be effective against exposed mites, those hiding in brood remain unaffected; which means the mite reproduction cycle is not really broken.
That said, we at Abbigail Honey will be using Oxalic Vapor in the coming weeks as the first spring treatment.
Are there temperature considerations to effective use of Oxalic Vapor?
The only temperature restriction is that in place is that you need an outside air temperature of 2.78 (3) Celsius during the treatment and for a few hours afterwards. There is no upper temperature restriction.
Will the vapors contaminate my comb?
Oxalic Vapor does not contaminate comb, bees or brood.
What is the best course of treatments for a mite spike or mite population explosion?
Should you be treating for a mite explosion, remember to treat 3 times over a 15 day period, or once every 5 days times 3 treatments.
How much Oxalic Acid powder do I use per treatment?
There are very clear directions on the packaging for proper use, but it is generally ¼ tsp per full brood box. Be as accurate as possible with measurements.
How do I optimize the treatment?
You should do your best to seal the hive during treatment and then keep it sealed for about 10 minutes after treatment.
Finally, DO NOT use oxalic Vapor treatments with honey supers in place.