Varroa checks

[Ben Framed]

Nigel I can see where it is surprising to you, not being the traditional approach. It was for me as well until Beeboy01 did an experiment back a couple years ago, all the while keeping us updated of the findings as he went along. Coolbees did a similar experiment reporting his findings here on this very same topic, reporting way back in Reply #13.  (I realize there has been a lot of ground covered in this interesting topic). Go back and take a look at his interesting findings.

I tried to find beeboy topic as well and with the intention of posting its reference here for you but so far I have not found it. Good stuff uncovered here by both of our fellow members! I am glad you have joined us here at beemaster as well. Your input is very helpful and appreciated!!!

Phillip

[Beeboy01]

Nigel, I try to cover two complete mite life cycles with my treatment regime. Since mites spend about ten days in the capped brood during their breeding cycle I look at a minimum of 20 days worth of OAV exposure to be my target for a total treatment. I decided on a three or four day period between treatments from research which said that OAV crystals are removed from the hive by the bees in that time period so extending the time between treatments will only allow the breeder mites time to move over to another brood cell and continue the breeding cycle. A shorter period between treatments will keep the level of OAV crystal higher and more stable in the hive which increases it's exposure to the mite population and break the mite breeding cycle similar to treating the ground under the hives to break the small hive beetle life cycle by targeting their larval form.

   One thing that hasn't been brought up concerning OAV is the type of applicator used and how much is applied to each hive during a treatment. I am using a wand with a 1/4 tea spoon of oxalic acid powder which is about two grams applied through the screened bottom board. The application time takes about five minutes for complete vaporization and I'm usually treating a double ten frame deep. I've always wondered on the dose strength and application time with equipment like the ProVap and other similar designed applicators which from my understanding apply the OAV directly into the hive body and brood area. I would think that a quicker application using a larger amount of oxalic acid directly into the brood area would have a longer "half life" and be more effective in the hive but I haven't been able to find any research covering it. Of course there would have to be a point of diminishing returns with larger doses along with potential damage to the bees.
 
  I also agree with you that my treatment regime is labor intensive and not feasible for any large scale operation. I'm just a hobby bee keeper and run about 5 hives which are kept behind my shop which allows me to treat more often than most. 

[NigelP]

Nigel I can see where it is surprising to you, n

Ben, the surprising bit was the magazine article suggesting OA caused problems with bees. It can if dribbled in a solution, but to date I'm not aware of any serious affects recorded from vaporized OA.
Beeboy1, thanks for the clarification, same ideas here,  I just cover less cycles as less work (lazy moi  ). It's impossible to kill all varroa, my aim is to keep numbers low and below a supposed threshold (whatever that happens to be) that causes serious issue for the bees.

[Ben Framed]

Nigel I can see where it is surprising to you, n

Ben, the surprising bit was the magazine article suggesting OA caused problems with bees. It can if dribbled in a solution, but to date I'm not aware of any serious affects recorded from vaporized OA.

I know I was surprised as well. I'm not so sure about that part just yet......???

[NigelP]

   One thing that hasn't been brought up concerning OAV is the type of applicator used and how much is applied to each hive during a treatment. I am using a wand with a 1/4 tea spoon of oxalic acid powder which is about two grams applied through the screened bottom board.

A very important point.
I (rightly or wrongly) describe the OA vaporisers as of two type. Passive, as in the pan under mesh floor or inside hive floor under frames. Here  you rely on the sheer volume of vapour produced to fill all the hive.
The other type I describe as active. Like the sublimox I use, or any vaporiser where the vapour is forced out of a confined space under pressure These in my opinion are quicker and more efficient as they are blowing and forcing the vapour throughout the hive. With the proviso that the jet of vapour is not hitting a solid surface immediately after it leaves the nozzle.
I estimate at just over  a minute per hive using these types, 30 seconds for sublimation of 2gms of OA and another 30 to let it settle down wards from my eke.

[Ben Framed]

   One thing that hasn't been brought up concerning OAV is the type of applicator used and how much is applied to each hive during a treatment. I am using a wand with a 1/4 tea spoon of oxalic acid powder which is about two grams applied through the screened bottom board.

A very important point.
I (rightly or wrongly) describe the OA vaporisers as of two type. Passive, as in the pan under mesh floor or inside hive floor under frames. Here  you rely on the sheer volume of vapour produced to fill all the hive.
The other type I describe as active. Like the sublimox I use, or any vaporiser where the vapour is forced out of a confined space under pressure These in my opinion are quicker and more efficient as they are blowing and forcing the vapour throughout the hive. With the proviso that the jet of vapour is not hitting a solid surface immediately after it leaves the nozzle.
I estimate at just over  a minute per hive using these types, 30 seconds for sublimation of 2gms of OA and another 30 to let it settle down wards from my eke.

Nigel, You might be interested in a topic posted here some time ago.  Title: "OAV too hot?"
Some interesting twist there...

[NigelP]

Search for "OAV too hot?" retuned no hits Ben....if you could link it up, be interested to see what what was said

[Beeboy01]

Here's a quote found on page 15 of the Oct 2021 Bee Culture form Jerry Hayes

 " Lets say you have a parasite the size of a rat. You can't get it off and I can't help get it off either. So we come up with a plan. I'll lock you in your closet and we will vaporize a caustic acid in the closet with you. We do it. I open the door and the parasite the size of a rat has fallen off. Good deal. But you have burns on  your skin, your nasal passages are burned along with the trachea from breathing the stuff. Some of your eyebrows are burned off and your eyes are red and watering because of the acid burn"

Anyways Jerry continues on in the Study Hall section about RNAi as a control for the mites by using genetic modification which is being developed by Bayer Pharmaceuticals.

   When I first move to Florida I had the honor of meeting Jerry when he was the local apiary inspector for the state of Florida and I don't mean this post to show any disrespect to the man, he's probably forgotten more than I know when it comes to bees.  I'm just wondering if a statement like this could drive some bee keepers away from oxalic acid treatments causing disastrous results to their bees. 

[Ben Framed]

Search for "OAV too hot?" retuned no hits Ben....if you could link it up, be interested to see what what was said

Sending a PM

[Ben Framed]

I have read the hard exoskeleton of bees are not affected, nor the breathing passages. Where in contrast the soft tissue of varroa is the advantage of OAV. I wish I could find that. It is here somewhere in the archives along with links.

[CoolBees]

.... But you have burns on  your skin, your nasal passages are burned along with the trachea from breathing the stuff. Some of your eyebrows are burned off and your eyes are red and watering because of the acid burn"

Anyways Jerry continues on in the Study Hall section about RNAi as a control for the mites by using genetic modification which is being developed by Bayer Pharmaceuticals.
...

...  I'm just wondering if a statement like this could drive some bee keepers away from oxalic acid treatments causing disastrous results to their bees.

I have a hard time with this analysis of Jerry's. Bees aren't humans - the comparison is invalid in so many ways. Further, bees target and harvest oxalic acid on their own, or so I've read. I'd guess your conclusion was correct. No one makes money off of OA, it's too cheap. There are many that would like to find a "more profitable" (for them) solution to the Mite problem.

[rast]

Also having met and listened to him, Jerry never did like OAV from the get go.

[Ben Framed]

For any of you newer members the following article goes hand and hand with this topic, (a sister topic if you will allow), in case you may be interested.

Phillip

Has Anyone Used the Randy Oliver Shop Towel Mite Treating Method?

[NigelP]

Here's a quote found on page 15 of the Oct 2021 Bee Culture form Jerry Hayes

 " Lets say you have a parasite the size of a rat. You can't get it off and I can't help get it off either. So we come up with a plan. I'll lock you in your closet and we will vaporize a caustic acid in the closet with you. We do it. I open the door and the parasite the size of a rat has fallen off. Good deal. But you have burns on  your skin, your nasal passages are burned along with the trachea from breathing the stuff. Some of your eyebrows are burned off and your eyes are red and watering because of the acid burn"

Thanks for that Beeboy01, Looks like total rubbish written by a supposed expert, I'll bet the farm he provides no evidence of what he claims.  It's been tricky to get definitive prove of how vaporised OA crystals kills varroa, but it is thought that OA vapors enter through the soft pads of the mite's feet and travels to the blood stream, effectively acidifying the mite and thus killing them. It is also thought that it destroys parts of the mite's mouth. However it works, it decimates them.
There is little evidence of of vaporised OA having any major detrimental effect on bees and the RNAi treatments are still a pipe dream.
But OA vaporisation is "hot" topic. I had to resign from a local association as they refused to let me talk about OA sublimation in a talk I was giving to the members. Naturally I refused to back down.

[Beeboy01]

Nigel, I try to keep my mouth shut about different mite treatments but sometimes when an expert spouts something that is baloney I speak out. I've been bee keeping for over 30 years and remember it before mites. Since they arrived I've tried just about all the commercially available treatments and really think OAV is the best but as was mentioned the big companies can't make any money off it. Even suggesting shortening the intervals between treatments gets a large blow back in the local club I'm a member of.     

[Ben Framed]

Beeboy I appreciate you speaking out. This is how we all learn. Sometimes we speak out with good information, sometimes our references might be disputed;  but all in all it?s healthy in my opinion. I applaud you. You are very knowledgeable and I have learned a lot of good things from you. Keep up the good work!

Phillip

[Beeboy01]

Ben Framed, thanks for the complement, I'm just a hobby bee keeper and i know that I don't know a lot. Trying to shake off a day at the local flea market selling honey and educating people about local honey and bee keeping. Man it was hard work explaining where the different flavors of honey come from. I had a good year with over 30 gallons of mixed honey and need to move some to make room. Looks like I'll be a regular at the flea market for a few months. Not complaining, it's just another aspect of bee keeping I haven't have had to do before.   

[Ben Framed]

Though I would bump this for the sake of newer beekeepers. Good stuff here. In fact I would suggest reading the whole topic.

Nigel I can see where it is surprising to you, not being the traditional approach. It was for me as well until Beeboy01 did an experiment back a couple years ago, all the while keeping us updated of the findings as he went along. Coolbees did a similar experiment reporting his findings here on this very same topic, reporting way back in Reply #13.  (I realize there has been a lot of ground covered in this interesting topic). Go back and take a look at his interesting findings.

I tried to find beeboy topic as well and with the intention of posting its reference here for you but so far I have not found it. Good stuff uncovered here by both of our fellow members! I am glad you have joined us here at beemaster as well. Your input is very helpful and appreciated!!!

Phillip

... Treatment day 1 then wait till day 7 retreat. The problem is Varroa exiting their capped cells between days 2 and 6....

I also do 3-day treatment cycles with OAV, for exactly the reason you state. Only, I usually try to treat 9 times (27 day total).

I did mite counts and sticky board drop counts on every hive during treatment - for 2 years. I collected all the data. Based on that data, I now: treat in August (once yearly) & don't count mites. This is what has worked for me, in my area. My bees don't get a brood break due to winter, but they do have a dearth from August till November.

My average mite drop counts would look like this (counted on the 3rd day after each treatment, just prior to the next treatment):
900
900
900
450
300
300
280
320
18

As you can see, the last 2 or 3 treatments seemed to catch a goodly qty of mites, before the drop counts really fell.

I know they say that OAV "stays effective" for 3 days, but my notes showed very little increase in mite drops after about 30 hours post-treatment. Suggesting to me that efficacy drops off quickly.

My data definitely has proven - to me - that a 7-day OAV treatment cycle would not work. Fwiw.