Sublimation

[fiftyjon]

Use a pair (or three) small 12v batteries connect them in parallel to give more power than the single unit.

 

[Gilberdyke John]

I have a feeling the reason a car battery is suggested over a motorcycle is that most beeks have them to hand, well in their car and most beeks that have out apiaries would drive to them most times I would think. The cost of the varrox is also quite high the big t sells it at £132 so not something most small beekeepers would buy I would think. your looking at the total cost of over £160 with cost of mask which is getting very expensive for a 1 or 2 hive owner, but a beeks with 20 or more it would seem more viable.

Step forward the ubiquitous Land-Rover ;-)

 

[dpearce4]

When we had this talk it made me think about maybe using sublimation in the summer aswell. I have thought about using OA for a summer treatment when the bees have been split for a artificial swarm but decided against it as the bees wouldnt be in cluster so would be so much more difficult to do. But with sublimation as long as there is no sealed brood (you can do this when doing the AS by just placing open brood in the queen right hive and giving them a day or so to make sure they don't then decide to swarm anyway. then late in the evening when all flying bees are home do the treatment.

It seems a good way of treating to me.

 

[dpearce4]

Step forward the ubiquitous Land-Rover ;-)

damn forgot that.

 

[The Drone Ranger]

Or a 12volt motorcycle battery at much less weight. The heating cycle is quoted as 2.5 minutes so consumes 5.2A-h. Nowhere near car battery capacity unless you are doing a number of hives.

Hi sorry I just looked at the number of hives the OP has and thought a car battery is needed
I find about 5 or 6 hives starts to flatten the battery and the lead acid ones are best recharged well before they are flattened (about 50%)
You get the leisure batteries which deep cycle without damage but they are dearer and heavier (leastways mine was )

 

[user 6228]

At the temperature this thing works at what is stopping the oxalic acid generating carbon monoxide?

 

[Hivemaker.]

At the temperature this thing works at what is stopping the oxalic acid generating carbon monoxide?

Quote...

How does oxalic vaporization work? In the CRC Handbook of Chemistry and Physics we find that upon heating oxalic acid, the water of hydration boils off first, then at 315°F the oxalic acid starts to sublime (go directly from solid to vapor), and finally at 372°F any oxalic acid which has not yet sublimed decomposes to formic acid and carbon monoxide. The hot vapor rises within the confines of the hive bodies, and recondenses into tiny crystals that coat everything inside the hive. One of the problems with some vaporizers is that they get too hot too quickly and decompose, rather than evaporate the acid.
............................................

The equipment i use has a thermostat which keeps it at the correct temperature.

 

[Heather]

Step forward the ubiquitous Land-Rover ;-)

Path in wood is 4'wide... My Kia 4x4 wouldn't make it either.

But thanks for all the feedback, lots to consider here. And if more gentle treatment for the bees whilst hitting the varroa hard, I will go for it.

 

[Davelin]

Step forward the ubiquitous Land-Rover ;-)

Certainly needed one last year!

 

[nemphlar]

Is the poor temperature control the concern when using a copper pipe and a blowtorch, this seemed the cheaper ,lighter and quicker option

 

[user 6228]

Is the poor temperature control the concern when using a copper pipe and a blowtorch, this seemed the cheaper ,lighter and quicker option

On the beemaster forum someone managed to kill several hives with copper pipe method

 

[The Drone Ranger]

You will need a very good mask for the copper pipe method I think

If you are using the vapouriser and there is a slight breeze you just clip it on and stand upwind , 3 or 4 mins later nip in disconnect one clip (use mask) - wait another 10 mins or so - mask on retrieve vapouriser - leave the foam in the entrance - move on to next hive
Just start with the hive that's furthest downwind

 

[nemphlar]

Did they understand why, was it co poisoning

 

[sunhivebee]

I am surprised to hear that the device for oxalic acid evaporation is so expensive now; mine cost about 30 quid from some supplier in Germany; in the days when I used it on my hives, I did so without any protective gear, because by the time the crystals heat up and vapourizing starts, you are well advised to be elsewhere. And you don't approach the hive to remove the device until the process is finished.
The method seems a little less harsh than opening up and trickling cold acid on the bees in midwinter. But please, don't quote me as advocating no protection, I only talk about what I did in my days of treating for varroa.

 

[Heather]

I have always got OA for trickling to a tepid temp for bees , but research seems to show better results with vapour

 

[Smokeyred]

I would advise you to get a full face mask if possible, Heather.

But if you need a face mask, wouln't it be too strong for the bees?

 

[dpearce4]

lots of info here about oxalic acid http://en.wikipedia.org/wiki/Oxalic_acid

 

[Ely]

Much cheaper to carry on trickling in my opinion. Not sure I understand the logic of vapourising being less harse. If I was a particularly moody bee at time of treatment I know which I'd prefer to fend off between a beekeeper trickling and a red hot vapouriser. So you have to lift off the roof for 30 seconds or so midwinter? It really isn't a big deal. Especially when paying a fortune on unnecessary equipment is the alternative.

 

[itma]

Yes, Rich.. I have successful trickled,reduced varroa to keep the hive very viable .. but the university research seemed to prove that there was a higher loss of varroa with a lower dosage of OA and I felt that must be beneficial to my bees, so worth a shot.
...

OK veg, will give it a go then....please dont mention Health and Safety

If this is the LASI research, the difference between the varroa kills with sublimation and trickling was EXTREMELY marginal - iirc from the open day it was something like the difference between 94 and 96%.
LASI would make the point that UNLESS you followed their protocol of culling sealed brood before treatment, then you would be wrong to expect "statistically significant" differences between the two methods.

The quantity of Oxalic that is used is pretty irrelevant (its cheap and small quantities biodegrade in the soil).

It is concentration (rather than simple quantity) that to me is a better indicator of its potential for harm
I don't want 1 gram of Oxalic crystals on my bare skin.
Dissolve that same 1 gram in a bathtub full of water, and I wouldn't worry about dipping my hands in it.
Sublimation is about putting Oxalic crystals all over everything, including bees, in the hive. Seems 'nastier' to me.


The LASI conclusion was that **for large scale operations** where the cost of the kit is spread over lots (hundreds?) of hives, and speed of treatment matters (a lot), then sublimation is the way to go.

In conversation, they suggested that Associations might hire out the protective equipment to members.
But Mr Garbuzov had no idea how any question of liability for injury or whatever might be handled.
They used a full-face (mouth, nose AND eyes) gas mask for their research - but didn't know how much it had cost.

There was a recent thread here that highlighted a comparative Health & Safety analysis between Oxalic spraying (yes, not trickling) and sublimation.
That report suggested that a disposable £12 mask was probably adequate, and the £15 (again disposable) mask specification wasn't strictly needed.
For 8 hives, even at £12, that's an extra £1.50 per hive for the mask alone!



Again in conversation at the LASI open day this summer, Garbuzov readily accepted that trickling was a much more rational solution for the hobby beekeeper, being damn near as effective, with almost no overhead costs and much lower risks.
Have they changed their tune on that?

 

[Hivemaker.]

They ingest some of the treatment in syrup, causing internal damage which shortens their life, hence the recomendation to only treat once, unlike sublimation which can be used more often if needed.