Gavin, I think we have two posts going on here on same subject
Thanks. Did spot it last night but lost the internet for a while (found it again!). Welcome, Dave. G.
Gavin, I think we have two posts going on here on same subject
Thanks. Did spot it last night but lost the internet for a while (found it again!). Welcome, Dave. G.
Last edited by gavin; 15-12-2013 at 10:55 AM.
I bring along a flask of hot water to the apiary which I pour into a container. I stand the bottle of Oxalic in this before trickling so that I am not tipping a cold liquid over the bees.
The best temperature for trickling is a coldish day, 2-4 C when the bees will be tightly clustered.
If you apply Oxalic in mild conditions the bees won't be tightly clustered and they will occupy more seams which means that they will get a much higher dose of oxalic if you base the dosage on counting seams.
I'll be treating bees today, and showing anyone who turns up at the association apiary at 1pm. Trickle/dribble of course, so I have no experience to offer Dave. None of that namby-pamby warmed-up flasks stuff here - these are *Scottish* bees so they'll get it as it comes! The bees themselves will be cool (should be no brood), and the small volume per seam of bees will only temporarily change the temperature of the few bees hit by the dribble. They may already be at a temperature close to the inside of my car.
Might there be more brood than normal at this time of year? Really don't know. Not sure that some flying and a little pollen coming in means they're raising brood. Can anyone guarantee that in a month's time they'll be less likely to have brood?
Digging out brood before dribbling? That has to be very disruptive and there's no way I'd do that at this time of year. And as for sublimation being more efficient than trickling, I doubt that. I seem to recall published work that implies that it is slightly less efficient (in terms of % mites destroyed per treatment).
Trickling:
- fast and easy
- very little equipment needed (and it is light)
- you only treat the bees, not their furniture
- safe for the operator, wear gloves and take care not to splash in the eyes
- can just pour away spare solution on the ground
- can be scaled up to do large numbers using a sheep medication dispenser
- ideal time to check stores by looking down on frames (Bees at top? cells at top still with sealed stores? Heft it with roof off?)
- ideal time to put fondant on light colonies, straight on frames or better on QX (don't need it before now, about to start brood raising, you hope)
Sublimation:
- don't need to take roof off
- can repeat (apparently) but how do you know it needs it?
- needs equipment carried to your bees (car battery or source of heat as well as the vaporizer)
- requires fine particle face mask for anyone anywhere near (it is said there are records of beekeepers damaging themselves by inhaling oxalic)
- much of the oxalic acid lands on woodware and will remain there until the colony fills the box
- isn't well integrated with sorting winter stores issues
- folk say it is efficient for large numbers of colonies (but so is trickling)
Some LAs seem to go in for sublimation in a big way. Seems a big mistake to me to show novices a more dangerous way of treating your bees.
Last edited by gavin; 15-12-2013 at 11:35 AM.
I spent a while this morning trying to find a link to some research that came from LASI earlier this year (which I'm sure does exist). I think that it even made it's way onto the BBC website and into assorted papers too at one point which rated sublimation very highly and no doubt it was those findings which were driving Karin Alton's thinking. The problem, is that for some reason I can't seem to find any mention, anywhere. No references are coming up after several different searches.
I have experience of using both methods and in my opinion would forget the sublimation method. It is too much of a faff and on a health & safety point is far more dangerous to the operator due to the sublimation gas. The trickle method is cheaper and quick to do if you have to get around a number of hives. I usually trickle when the temperature is about 5 degrees and I don't warm the oxalic although it is not freezing cold either.
......
http://www.telegraph.co.uk/earth/wil...wrong-way.html
Took a while to find, I seem to remember there was a fair bit of discussion on the net at the time but strangely that it almost all concentrated on the couple of almost throw away lines at the end referring to crossing with African bees.Now researchers have found that when applied as a vapour rather than a solution, and at a particular dosage, the treatment can remove virtually all traces of varroa from hives without any harmful outcomes for bees.......
Results from the trials have not been officially published, but Prof Francis Ratnieks told the Telegraph that in the most effective format – a vapour at a particular concentration – the treatment was 97 to 98 per cent effective.
Last edited by prakel; 15-12-2013 at 12:09 PM.
Hi Dave
I use the Varrox vapouriser it's a bit dear but solid
The biggest supplier has gone nuts with its pricing and you get it much cheaper elsewhere
To make life easy this is the way I do it
The hive floor is an epoxy coated wire mesh above a solid floor with a varroa tray insert (similar to the link below showing Ian Craig's )
http://www.scottishbeekeepers.org.uk...a%20floors.pdf
You need to look at the last page to make sense of the next bit
The varrox vapouriser is inserted between the mesh and the solid floors once the tray is removed
floor.JPG
2g of oxalic in vapouriser from the back of the hive then close the slot with foam (cheap from Dunelm Mills)
Go round front plug the entrance slot with foam as well
I use one of these batteries because it has a charge indicator,a handle and it's not heavy
http://www.amazon.co.uk/gp/product/B...?ie=UTF8&psc=1
Anyway connect the leads and move upwind for 2.5 mins then disconnect the battery
Masks like SCOTT PRO2 with A1B1E1 filters are designed for organic acids
You might use something cheaper but at about £20 it is worth it if you are considering bent tubes and blowlamp madness
The coated mesh floor isn't affected by acid it disperses the vapour well and doesn't remove heat from it
You can slip the varrox past the foam and move on to the next hive after 10mins leaving the foam for another 10 mins
Hope that helps
DR
Last edited by The Drone Ranger; 15-12-2013 at 12:53 PM.
Hi Prakel
I have two of these batteries but one would do the job
I am told the varrox is about 150W
I have around 25 to treat
Here's the calculator
http://ep.yimg.com/ty/cdn/sports-imp...drainCalc.html
here's a quick overview as well
http://www.youtube.com/watch?v=MKDdrmM4UqY
http://www.thebeebusiness.co.uk/varrox.php
Why two batteries well you can only safely drain a car battery to about 50% before recharge
Leisure batteries are not so restricted but heavier
graph.jpg
Last edited by The Drone Ranger; 15-12-2013 at 01:06 PM.
Hi DR, thanks for the calculator link. Was just wondering about usage in some out of the way (badly chosen) apiaries. Not that I expect to be starting to use sublimation any time soon. Must say though that I did give the subject a second glance the other week when a UKbeek posted a video of a (Italian?) vaporizer which he uses, on Beesource.
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