Full Answer
Should treatment regimen for OAV when brood is present be based on 24-day?
Nov 19, 2021 · However, oxalic acid vaporization is most effective when there is little or no brood in the hive. This is not always possible for Southern beekeepers. late Fall or early Winter; before honey supers go on the hive in early Spring; for new hive splits with little capped brood; mid-late Summer (3 treatments required)
Why is Oa vapor not recommended during brood rearing?
Jun 01, 2020 · The treatments were: 1) OA vaporization applied once, 2) OA vaporization applied three times over three weeks, 3) brood interruption for 24 days, 4) OA applied once + brood interruption, 5) OA applied three times + brood interruption, 6) no OA or brood interruption as a negative control, and 7) treatment with amitraz (Apivar) as a positive control.
How many oxalic acid vaporization treatments for brood?
Jun 16, 2017 · Treat on day 0, treat on day 4, treat on day 8, treat on day 12. The 4th treatment on day 12 will kill mites through day 15. This treatment schedule covers 14 days, with a substantially reduced period of in-effectivty between treatments. Of course, treating the hive when broodless is by far the best procedure when using OA.
How often do you treat OAV?
May 01, 2014 · Brood is capped for between 12-14 days ( workers & drones ), less on small cell; Varroa mites stay in the phoretic state (on the bees) for on average 7 days between breeding cycles; Oxalic acid vaporization is considered 95% effective on phoretic varroa mites
How often can you do a oxalic acid treatment?
They treat once in the Winter when colonies are naturally broodless, and once again in the late Summer after inducing an artificial state of broodlessness by caging their queens for 21 days.May 25, 2015
How often should I treat for varroa mites?
At least for now, any one interested in keeping bees must have a plan to deal with this external pest of the honey bee. Beekeeping involves hive management and varroa management. When do you need to worry about varroa mites? For most beekeepers, it is a necessity to treat bees for varroa mites several times a year.Dec 9, 2021
When should I treat my bees with oxalic acid?
WHEN IS THE BEST TIME TO USE OXALIC ACID TO TREAT? The most effective time to treat a hive with Oxalic Acid is when a hive has little to no sealed brood. It cannot penetrate capped brood so it will have no effect on the next generation of mites that were left in capped brood.
How long does oxalic acid solution last?
If you must store your oxalic acid-containing syrup for any length of time it should be in the fridge (4°C). Under these conditions HMF levels should remain well below toxic levels for at least one year. However, don't store it for this long … use it and discard the excess.
Is it too late to treat for varroa mites?
If you're wondering if you still can, the answer is yes! Although late summer treatment is the best for protecting your winter bees, a delayed treatment is better than no treatment. Whenever you need to treat for varroa, you have to consider which treatment is the best for the time of year and the status of your hive.
How many varroa mites is too many?
It would also seem that Varroa are transmitting more virulent strains of viruses with each passing year. Because of this, I recommend to keep mite levels below 1 mite/ 100 bees in the spring and below 3 mites/100 bees in the fall. With Varroa loads any higher, beekeepers risk high colony losses.Sep 26, 2018
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.Mar 10, 2021
How much oxalic acid is in a brood box?
one gramHow much Oxalic Acid is used in the OAV process? The recommended dosage is one gram per brood chamber. Most have two brood chambers, so use two grams (which is very close to V2 a teaspoonful. You could use a 12 teaspoon measure in lieu of two one gram (V4 teaspoons).
How do you vaporize bees with oxalic acid?
1:335:37How to Use an Oxalic Acid Vaporizer to Treat Honeybees for Varroa MitesYouTubeStart of suggested clipEnd of suggested clipThe manufacturer recommends you do a test vaporization to know exactly how long a quarter teaspoonMoreThe manufacturer recommends you do a test vaporization to know exactly how long a quarter teaspoon of oxalic acid will take to completely vaporize. Once you put it in the hive in our case.
How late can you treat bees for mites?
To raise healthy bees in September and October, your colony needs to be virtually mite-free by the end of August, the very month that the mites-per-bee ratio explodes. So if you are going to treat your hives, August is the month to do it.
Can you eat honey treated with oxalic acid?
The honey is not at all unsafe to consume. The treatment for varroa mites using oxalic acid is permitted by the EPA with a condition that supers not be in place during the treatment process.Jul 23, 2016
How effective is oxalic acid?
It has been shown to be a direct and effective treatment for Varroa mites and has been used for this purpose in Europe and Canada for many years. It was only approved for use in beehives in the US in 2015. Oxalic acid isn't terribly expensive, is natural and can be very effective.
How to vaporize oxalic acid?
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 to use oxalic acid in a hive?
Dribble Method of Using Oxalic Acid. In the dribble method of using oxalic acid, the acid is mixed with warm 1:1 sugar water (equal parts of sugar and water). Then, the mix is sucked up into a syringe applied between the frames in the hive – directly wetting the bees.
What is the best way to control varroa mites?
Oxalic acid is an organic compound that aids beekeepers in the fight against varroa mites. With the use of a special heating wand, Oxalic Acid Vaporization is one of the best tools for control varroa control. A naturally occurring substance, oxalic acid, is an effort to step away from the use of synthetic chemicals in beehives.
Can vaporization damage a varroa?
It may also damage varroa mouth parts. With vaporization we are not trying to coat the bees, rather we are injecting the heated vapor into the hive. As the vapor cools, small crystals are left behind on the bees, comb and hive walls. As worker foragers come and go-they will be exposed to the crystals.
Can you inhale oxalic acid in a vaporizer?
This is an overview of one way to use oxalic acid with a vaporizer in your bee yard. Please use appropriate safety gear to protect your skin and lungs. Do NOT inhale the vapor – do not.
Is OA good for bees?
Oxalic Acid (OA) has been used by European Beekeepers for many years. With reports of 90-99% efficacy in killing mites, they found it be a useful tool in the fight with varroa. It was only approved for use in the US in 2015. Products available in stores are labeled for use in beehives. Some beekeepers use generics too.
Is oxalic acid safe for bees?
Safety Precautions When Using Oxalic Acid. Oxalic Acid is safe to use for the beekeeper and the bees as long as proper safety protocols are used. Follow the instructions on the label – you will need a properly rated acid gas respirator. An N95 is the standard.
How far apart should I treat a brood hive?
oxalic acid is approved only for treating a broodless hive, so this is just a theoretical question: For OAV'ing a hive with brood, the rule of thumb I have heard is 3 treatments 7 days apart, or 4 treatments 5 days apart.
How long should I wait to treat a broodless hive?
oxalic acid is approved only for treating a broodless hive, so this is just a theoretical question:#N#For OAV'ing a hive with brood, the rule of thumb I have heard is 3 treatments 7 days apart, or 4 treatments 5 days apart. The idea being, that since OAV doesn't kill mites in the sealed cells, you have to repeat treatments to get the mites as they emerge from cells that were sealed before OAV'ing started.#N#The general idea makes sense, but I don't understand the reasoning behind the timing . . . ?#N#Workers are in sealed cells for 11 days, and drones are in sealed cells for 14 days. I am sure I am just being dumb, but wouldn't this mean that any series of OAV treatments to get all the emerging mites would need only span 14 days? In other words, OAV'ing over a period of 20 days or 21 days is longer than needed, and is actually counter-productive because it has the effect of "diluting" the treatment.#N#Add in the fact that OAV seems to lose effectivity after 3 days, and it seems to me that if one were planning on doing a total of 4 OAV treatments, wouldn't it be better to spread those 4 treatments over the 14 day period for all capped brood to emerge rather than the aforementioned 20 days? Put another way, 4 treatments spaced 4 days apart would provide almost continuous effectivity for the time period for any and all capped brood to emerge, which would kill more mites than a treatment schedule having gaps of effectivity?#N#Just wondering out loud . . . .#N#.
How to use oxalic acid for bees?
The “Drizzle” and “Spray” methods of application use oxalic acid disolved in sugar syrup, which the bees then ingest. “vaporisation” involves heating up a small amount of oxalic acid dihyrate within the hive using a special device. The oxalic acid dihyrate first liquifies and then becomes a gaseous vapor which permeates the whole hive. The vapor quickly re-crystalises on all the inner surfaces of the hive and the bees as a fine coating of oxalic acid crystals. These crystals are deady to mites. In a heavily infested hive you can expect a drop of over 1000 mites in the first 24hr, but the treatment will remain effective for up to a week and you will see a continued but diminishing drop over the next few days.
What temperature do bees fly?
Make sure there is not too much wind and pick a time when there are not to many bees flying. The temperature should be above 4° C. You will need at least the following items:
How long does a varroa mite stay in a phoretic state?
Brood is capped for between 12-14 days ( workers & drones ), less on small cell. Varroa mites stay in the phoretic state (on the bees) for on average 7 days between breeding cycles. Oxalic acid vaporization is considered 95% effective on phoretic varroa mites.
What is the best treatment for varroa mites?
Oxalic acid vaporization is currently my varroa mite treatment of choice. There are several techniques using oxalic acid, spraying, drizzling and vaporization. Most research indicates that vaporization causes least damage to the bees and is the most effective against mites. However all the techniques work well, ...
Is oxalic acid vaporizer safe for bees?
Oxalic Acid Vaporization is potentially more hazardous to beekeepers than other oxalic acid methods. Vaporizers can be an expensive initial outlay – costing up to £100. Slower than “Drizzle” method. Like all “acid” treatments, not effective against mites in brood.
Is oxalic acid vaporization effective?
Oxalic Acid Vaporization is over 96% effective ( without brood) Oxalic acid naturally occurs in the hive and is considered an “organic” treatment in the UK. Unlike other oxalic acid methods, repeat treatments can be given without damaging bees. Do not have to open or disturb hive. No known negative effects on bees or brood.
Is varroa treated with brood?
Generally this treatment is best done when there is little or no brood because it is only really effective on varroa in the “phoretic” state (on the bees). Varroa in with the brood are generally protected from the effects of the treatment.
How to use a 12 volt vaporizer?
To use a 12-volt passive vaporizer, the beekeeper measures oxalic acid crystals (from 1-3 grams) into the cooled vaporizer, shoves the device into the entrance, seals the hive entrance up with foam or rags, then energizes the vaporizer with a power cord from the truck battery.
How to apply oxalic acid to bees?
Although the dribble method of application is nearly universally (except in the U.S.) recommended, there are also other ways in which oxalic acid may be applied: 1. Kitchen recipes and backyard tinkering with shop towels, etc. 2. Heat vaporized within the beehive.
What chemicals evaporate at room temperature?
Some chemicals used in beekeeping, such as thymol, menthol, PDB mothballs, and formic acid readily evaporate or vaporize at room temperature. Oxalic acid, on the other hand, requires high heat to vaporize.
Does OA vaporize?
Oxalic acid, on the other hand, requires high heat to vaporize. Once vaporized, though, OA can disperse throughout the colony, and then recrystallize into a fog of tiny crystals that attach to all surfaces (wood, comb, bees’ bodies, etc.).
Is OA dribble bad for bees?
There are two problems associated with OA dribble: (1) it requires opening the colonies for the fall/winter treatment, and (2) there are issues of bee toxicity and depressed broodrearing due to bees ingesting some of the syrup. Both these issues can be circumvented by applying the acid in vapor form .
Is vapor dispersion toxic to bees?
This vapor dispersion has the advantages of exposing the majority of phoretic mites to the tiny crystals, and there is no incentive for the bees to ingest it, since it is not mixed in sugar syrup, thereby minimizing any toxic effects it may have on the bees.
Is it safe to use a vaporizer?
Manufacturers of vaporizers claim, of course, that vaporizers are safe to operate . German researchers, Gumpp, et al. (2003), state that “By appropriate use there is no risk to the health of the apiarist.”.
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.
How long can OA syrup be stored?
Solutions can be stored for a maximum of six months at a storage temperature of 59 degrees.
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.
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.
Is OA good for broodless?
Research clearly demonstrates that OA is most effective in broodless colonies for both the trickle and fumigation techniques.
How often do beekeepers treat their bees?
Because oxalic acid does not affect capped brood, beekeepers treat their bees 3 to 5 times in two weeks, so that one brood cycle is covered completely to catch every mite.
How does the vapor method work?
The vapor method works because the vapor condenses on the bees. The dribble method works because bees communicate and groom by touching each other. They quickly spread the stuff around the hive. Endless discussion has centered around which is better, which is safer for the bees, which kills more mites, and on and on.
Can you open a beehive in winter?
The main danger with opening a hive in winter is chilling the brood. But the whole point of applying oxalic acid in winter is to use the broodless window to kill the most mites. So with no brood in the hive to start with, a couple minutes of open time will not hurt anything.
A Word About Safety
Timing The Treatments
- In the rest of this discussion, I’m assuming that there is little or no residual activity after an oxalic treatment. A publication by Dadantstates “The hive returns to pre-treated levels [of oxalic acid] shortly after treatment. Within days of vaporization, the bees will remove the residual OA crystals from the hive.” Is there enough oxalic acid in the hive during the removal stage to kill emerging …
Varroa Under The Cappings
- Now let’s say you treat on July 1. Theoretically, all the phoretic mites will die in the next day or two. But you have approximately twelve days of varroa mites that are preparing to emerge. Why twelve? Because the brood develops in three stages. Brood is in the egg stage for 3 days, the larval stage for 6 days, and the pupal (capped) stage for 12. The rule of thumb here is that each …
Tracking The Emerging Mites
- To reiterate, after the first treatment you have a shed load of dead mites and 12 days-worth of safely capped mites. During each of the next 12 days, some of the mites will emerge along with the brood. These emerging mites are mated and ready to go. Presumably, they attach themselves to a honey bee and ride around until they are taken to a ready-to-cap brood cell. They detect this…
Alternative Choices
- If I were doing this, I might consider using a five-day interval and then a six-day interval since there is no reason the intervals need to be equal. That means I would treat on day 1, then five days later on day 6, and then six days later on day 12. Anyway, it’s just an idea that may or may not make any difference. This post is just a roundabout way of saying I don’t have a good answer to the questi…