Beekeepers who use oxalic acid foggers to administer the acid in solution for Varroa
Varroa destructor
Varroa destructor is an external parasitic mite that attacks and feeds on the honey bees Apis cerana and Apis mellifera. The disease caused by the mites is called varroosis. The Varroa mite can only reproduce in a honey bee colony. It attaches to the body of the bee and weakens the bee by sucking …
What is oxalic acid vaporization for bees?
With the use of a special heating wand, Oxalic Acid Vaporization is one of the best tools for control of this major pest of bees. A naturally occurring substance, oxalic acid, is an effort to step away from the use of synthetic chemicals in beehives.
Is oxalic acid safe for beekeepers?
Oxalic acid is several thousand times stronger than vinegar. It is bitter to the taste and irritating to the nose and mouth. Beekeepers should use proper protective wear when using this or any other acid.
Does oxalic acid kill mites on bees?
Oxalic acid treatments only kill phoretic mites. Those are the foundress mites that are riding around on the adult bees. Most of the time, the majority of mites in a hive will be inside the capped brood. Oxalic Acid does not kill mites under the cap.
How do you use an oxalic acid vaporizer?
Basically, you use a vaporizer which is a metal wand with a plate at one end and a cord which connects to a battery at the other end. One gram of oxalic acid is placed on the metal plate.
How much oxalic acid should I use?
It's a test to make sure the mask is properly seated on your face to give you full protection. Put on your goggles and gloves. Count the number of boxes on the hive, as this determines the amount of oxalic acid to use. The dose is 1/4 teaspoon per box, of any size.
How long do you vaporize oxalic acid?
How long does it take to vaporize OA? Vaporizers take 2.5 minutes to vaporize OA. The current is disconnected after the time limit and the vaporizer remains in the hive another two minutes to finish vaporizing.
Can you feed bees while treating with oxalic acid?
Any treatment applied indiscriminately can harm your bees and this is certainly true with oxalic acid. The approved use of oxalic acid in the hive - using the documented procedures and cautions - will be just fine. But don't deviate from that, since overuse can indeed be harmful to your bees.
How do you make oxalic acid vaporizer?
10:0717:22On that way once the cap is on and you tilt the unit right side up because i'll put the cap onMoreOn that way once the cap is on and you tilt the unit right side up because i'll put the cap on upside down like this once i tilt it right side up the acid powder is going to fall to the bottom.
At what temperature does oxalic acid break down?
It melts at 417-419° C. (with decomposition) when heated in a sealed tube (A. Michael, Ber., 1895, 28, p. 1632).
How do you dilute oxalic acid?
Mix one part oxalic acid with 6 parts warm water.
How do you use oxalic acid vaporization?
1:333:18Model you slide the vaporizer right into the entrance of the colony. And then you're going toMoreModel you slide the vaporizer right into the entrance of the colony. And then you're going to actually cover up the entrance of the hive.
How long does oxalic acid stay in hive?
How Quickly does Oxalic Acid Vapor Lose its Effectiveness? It is important that beekeepers note that oxalic acid from vaporization and fogging remains in the hive in doses that are high enough to kill mites for up to 3 days. After that, natural loss of strength makes the oxalic acid ineffective against mites.
Does oxalic acid damage brood?
Oxalic acid is known to cause damage to open brood (Terpin et al. 2019). Damaging brood during honey flow can weaken the colony later in the summer. We already have treatments that are labeled for use when honey supers are on and that work through the cappings—Mite Away Quick Strips and Formic Pro.
How do you use oxalic acid wand?
The most popular method of using oxalic acid is – “oxalic acid vaporization“. A small amount of Oxalic Acid crystals are placed on a special wand. The wand is inserted into the hive and heated to vaporize the crystals. There are many types of wands available to purchase.
How do you use Provap 110?
Use ¼ teaspoon per brood chamber no matter the size be it mediums or deeps, eight or ten frame. Use a ½ of a quarter teaspoon on a nuc. On a two brood chamber hive; you would use ½ a teaspoon. Invert the vaporizer.
How does oxalic acid treat varroa mites?
How to apply oxalic acid treatmentsCheck the strength of the colony.Multiply the number of occupied frames with 5 ml.Fill the right amount of the oxalic acid solution into a syringe.Slowly trickle it over the top of the combs. ... Close the colony and repeat with the next one.
When to apply oxalic acid?
Or, more accurately, when there is very little capped brood. For this reason, oxalic acid is often applied in late fall or over the winter.
What temperature does oxalic acid burn?
When heated to around 100 degrees C , oxalic acid burns off water, leaving anhydrous (water-free) crystals. When further heated to around 157 degrees C, sublimation starts, which is the transformation from the solid state to a gas.
What percentage of variola are in the phoretic state?
This, of course, has important implications for how and when it can be used. During the summer only about 15 - 20% of Varroa are in the phoretic state, meaning they are roaming the hive or attached to bees. The remainder are in a capped cell - out of the reach of oxalic acid.
How much oxalic acid should I add to a mixing container?
Measure 8.75 grams of oxalic acid and place into your mixing container. Add 6 fl oz. (about 150 grams) of hot water and stir until the oxalic acid crystals are fully dissolved (do not shake) Mix in 3/4 cup (about 150 grams) of sugar and stir further until dissolved too.
What is the oxalic acid molecule?
Herbivores find oxalic acid repellent, which is a handy property if you are a plant! Chemically, the oxalic acid molecule is comprised of two carbon, two hydrogen and four oxygen atoms. It is a colorless solid that dissolves to form a colorless solution in water.
How long should I wait to remove honey supers before putting them back?
Another an important note! Remove honey supers before applying oxalic acid and allow at least 14 days before putting them back, so that acid is cleansed from the hive, thus avoiding honey contamination.
Is summer a good time to apply oxalic acid?
The remainder are in a capped cell - out of the reach of oxalic acid. Therefore, the summer is often considered a less-than-optimal time to apply oxalic acid, since only a small percentage of the Varroa in the hive are "reachable". But that doesn't mean it cannot still be an effective treatment, as we will see below.
How to apply oxalic acid treatments
The most common way of applying oxalic acid is by trickling. For this, the oxalic acid solution is trickled with a syringe on the top bars of the frames at a dose of 5 ml per occupied frame. For instance, if your colonies occupies 5 frames, the right dose is 25 ml. If it’s on 8 frames you trickle 40 ml.
Good and bad applications
If I had to chose an application method, I would chose trickling. It’s quick and easy. If the handling with a syringe bothers you, there are also applicators which are easier to handle. Sublimating oxalic acid is as efficient and safe for the bees, too. However, the user safety isn’t as high as with trickling.
When to treat with oxalic acid
Now that you know how to treat, the next step is knowing the right moment. Oxalic acid acts only on the mites on the adult bees. Therefore, it’s a treatment for colonies without brood. This can be a natural break in winter or during drought periods in summer. But it’s also possible to produce an artificial break by caging the queen.
Sweet and sour – misunderstandings about oxalic acid treatments
The first available recipes or products for treating against varroa with oxalic acid by trickling always indicated that the solution must be prepared with sugar (sucrose, to be exact, the same sugar you use in cakes or your coffee). Beekeepers often think that it’s for making it more attractive for the bees.
An issue and a solution
There’s a caveat, though. Oxalic acid solutions with sugar don’t remain stable for long time. After a few days, the solution gets brownish. This is a sign that the sugar degraded in presence of the acid. The concentration of HMF, a substance that results when sugar degrades in an acid environment, increases.
Why you should know the science behind oxalic acid treatments
If you got this far: congratulations! It’s for a reason I told you all this science stuff: I want you to make good and informed decisions. Oxalic acid is the most efficient treatment we have against the varroa mite. Also the most flexible one. Beekeepers worldwide use it, in hot or cold regions alike.
How long does it take for a vaporizer to kill mites?
When it contacts the mites, it kills them. Each vaporizer is different. Some take only a few minutes to activate the acid, while others take a little longer. Since you don’t have to open the colony in order to treat, this seems to be the easier of the two methods to implement, especially on cold, rainy days.
How many mites per 100 bees?
The latest research suggests the economic threshold for Varroa is now three mites per 100 bees. In the old days, before the recently introduced viruses, small hive beetles, rising stresses from limited nutrition and growing toxin levels in the environment, upwards to 15 mites per 100 bees was considered tolerable.
Can you use 100% oxalic acid on bees?
If you start searching the internet for oxalic acid application in bees, there’s a whole host of information out there on recipes for taking 100% oxalic acid down (wood bleach) to the 2 or 3% recommended application concentrations. Some advice may be sound, but other advice can be reckless and dangerous to you and your bees.
Does interrupting the brood cycle help bees?
So, interrupting the brood cycle not only knocks down the mites (and the viruses vectored) prior to the Winter bees being reared, but reduces bee populations as well. Fewer mites equals improved health, and fewer bees equals less food consumed; both circumstances contribute directly to improved Winter survival.
Does phoretic mite work?
No; it only works on phoretic mites, i.e., those mites crawling around on the frames or adult bees. The mites breeding under the cappings of the brood cells are unaffected by oxalic administrations, as well as most other miticide products. Therefore, applications are most effective when no brood is present.
Is oxalic acid toxic?
Given its caustic effect on the eyes, skin and respiratory system, it’s labeled with the highest degree of toxicity, “Category 1.”. So, as with all pesticides, caution must be taken when handling it.
Is oxalic acid a fat soluble lipid?
Since it is not fat soluble ( a lipid), it doesn’t build up in wax comb. Back in 1957, it was registered as a pesticide (disinfectant/sanitizer), but, by 1994, the renewal of the product registration was cancelled. There are risks involved if you plan to use oxalic acid.
What is oxalic acid?
Oxalic acid is completely natural. It is a natural organic substance present in many plants, including vegetables, leafy greens, fruits, nuts, seeds, and others. Herbivores find oxalic acid repulsive, which is useful if you’re a plant!
Why is oxalic acid of interest to beekeepers?
It has proven to be a direct and successful treatment for Varroa ticks. People used it for this purpose for many years in Europe and Canada. It was only in 2015 that it was allowed to be used in beehives in the United States. Oxalic acid is inexpensive, natural, and has the potential to be very successful.
How much oxalic acid per hive?
The recommended dosage is one gram per brood chamber. Most have two brood chambers, so use two grams (which is very close to a ½ teaspoonful). You could use a ½ teaspoon measure in lieu of two grams (a quarter teaspoon). More is not better
Oxalic Acid vaporizing for Varroa mites
The use of vapor to deliver oxalic acid into the beehive is an efficient way. It makes use of the physical features of oxalic acid by sublimating it with heat. This necessitates the use of specialized equipment known as vaporizers.
Oxalic acid fogging for Varroa mites
The second way of treating Varroa mites with oxalic acid is fogging. Oxalic acid fogging delivers a considerable volume in a single application. It is quite quickly, allowing beekeepers to travel from one hive to the next in quick succession.
Oxalic Acid bees recipe
An oxalic acid fog is created with a combination of ethyl alcohol and oxalic acid. To 100ml of ethyl alcohol, 25 grams of oxalic acid powder or crystals are added. Stir the oxalic acid until it is completely dissolved. Depending on the degree of the Varroa mite infection, this is enough to treat 30 to 50 hives.
How to mix oxalic acid for bees
Many countries allow the use of oxalic acid to treat beehives for Varroa ticks. Once there, it is used in powder or crystal form. Beekeepers who use oxalic acid foggers to administer the acid in solution for Varroa mite control must appropriately mix the acid. During treatment, people often mix oxalic acid with water, ethyl alcohol, or mineral oil.
How much OA water to use for bees?
Early use of OA by European beekeepers involved spraying each comb of bees in broodless colonies with a 2%-3% OA water solution. The technique was effective but time consuming since each comb covered with bees had to removed and sprayed on both sides for control.
Who is the apiary inspector in Maine?
Please read and follow the label. Remember, “The label is the law.”. Tony Jadczak is the State Apiary Inspector of Maine, and oversees the second biggest pollination event in the Universe when thousands of colonies come to Maine each May for wild blueberry pollination. Previous article Ask Phil.
How long does it take for hives to sublimate?
It takes approximately three minutes for the OA to sublimate and it is recommended that the hives remain closed off for 10-15 minutes after treatment.
Is OA good for broodless?
Research clearly demonstrates that OA is most effective in broodless colonies for both the trickle and fumigation techniques.
Is oxalic acid dihydrate toxic?
Although OA is considered an organic mite control, it has a ìDanger-Poisonî signal word on the label meaning it is highly toxic and corrosive.
Is oxalic acid toxic to bees?
The toxicity of oxalic acid (OA) to Varroa has been known for nearly three decades based on experiments conducted in Asia and later in Europe. The initial tests compared spraying weak OA solutions on bees, trickling OA sugar syrups into honey bee colonies and OA fumigation (vaporization). All of these methods demonstrated very high efficacy ...
Does sugar help bees?
It is thought that the sugar solution adheres to bees better or the sucrose makes the solution more hygroscopic. During the 1990s European bee researchers tested the effects of different OA concentrations and syrup solutions on both the mite and bees via the trickle method.
How to vaporize oxalic acid?
Follow these steps to safely and effectively perform oxalic acid vaporization: Close up (plug or tape over) any upper entrance. Then remove the entrance reducer and give the bees a puff of smoke to loosen the cluster and get them fanning.
How long does it take for oxalic acid to vaporize?
If you have a screened bottom board, clean off and prep the sticky board before beginning the treatment. Expect to see the biggest flush of dead mites in 24-36 hours after treatment. Follow these steps to safely and effectively perform oxalic acid vaporization: Close up (plug or tape over) any upper ...
What temperature do bees vaporize?
Oxalic acid vaporization during the broodless period can be done in outside air temperatures as low as 37 degrees F, but a better range is in the mid-40s to low50s F. At these temperatures the bees will be clustered in the hive and stay during the process.
What temperature does oxalic acid sublimate?
Above the sublimation temperature of oxalic acid (314 degrees F) the remaining minor components of the material are only briefly in a vapor, before everything cools back down. As it cools back down, the oxalic acid forms a visible cloud of very tiny, spikey, crystalline, acid dust particles that are deposited all over the interior surfaces in ...
How to keep comb from hanging down from a hive?
If there was any comb hanging down from the frame, move the wand over to the side to avoid getting the hot pan close to it. Seal up the front entrance around the stem of the wand using paper towels. Make sure the wand remains level and flat on the floor of the hive.
Can bees withstand vaporization?
Unlike humans, the bees easily withstand exposure to the treatment. The bees will be fine and receive the enormous benefit of removing more than 95% of all varroa mites in the hive from just one treatment. Oxalic acid vaporization has been used for decades in Europe and has a proven record for bee safety and efficacy.
Can you remove a mask from a bee hive?
This completes the treatment for the hive and it is safe to remove your mask at this point, unless you have another hive cycling through the process. In cool weather the bees are unlikely to come out of the hive in any numbers when it is reopened after treatment is completed. In warmer weather they sometimes do.
An Effective and Popular Treatment
What Is Oxalic acid?
Why Is Oxalic Acid of Interest to Beekeepers?
How Does It Work?
Oxalic Acid Cautions
- Handle oxalic acid with care
Let's start with the easy-to-explain bit - you need to be careful around oxalic acid. It is irritating to the eyes, mouth and skin. It also has a bitter taste (we don't suggest you test that!). Indeed, it is labeled with the highest degree of toxicity, “Category 1”. Click here to see the EPA label for the u… - Avoid use during the honey flow
Another an important note! Remove honey supers before applying oxalic acid and allow at least 14 days before putting them back, so that acid is cleansed from the hive, thus avoiding honey contamination.
When Oxalic Acid Works - and When It Doesn't
Popular Methods For Applying Oxalic Acid