How to use Apiguard

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New Bee
Sep 10, 2009
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Hive Type

I am a new beekeeper. I bought a nuc in late June and got off to a bad start due to my queen being very small and not laying. It's a long story but now I have a good queen but a small colony. I have very few varroa but have bought some Apiguard. I have a mesh floor and I have heard that it should be covered and the crown board holes covered when the Apiguard is put in the hive. However, I am a little concerned about ventilation in the hive and the bees suffocating. The instructions on the packet don't say anything about blocking anything.
I know if you ask 10 beekeepers the same question you will get 10 different answers, but your comments will be gratefully received.
Many thanks.
hello and welcome to the forum.

if you do a quick search there is loads of threads with good info on this subject but the general consensus is because the thumol fumes are heavier than air they drop through the floor so you need to keep the varroa tray and possibly the entrance block in.

I know if you ask 10 beekeepers the same question you will get 10 different answers

Nah, you could get at least ten answers from half that number!!

Presumably small colony means small entrance, still defending against wasps and robbing bees? Firstly, will it make a difference? How has your varroah drop been during checks?
None or very few varroah will mean none or very little reduction in mites!

If you carry on and treat, you might find that one tray may be sufficient to last the course. The bees would not be likely to overheat or suffocate with the ventilation very much reduced as they would circulate the air by fanning. You may need to watch for bees leaving the hive and massing around the entrance - if they do you can increase the entrance size a little or much more, as there will be so many bees as to prevent wasps entering easily.

With thymol it is more to do with irritation than suffocation - remember full sized colonies live in trees with perhaps only a small entrance which is sometimes a fair way from the brood nest.

You may be better served by encouraging the queen to lay more brood at this time of the year. The UK is a long way from north to south and even east to west, which can make the seasons easily plus or minus a month, depending on location. Your location is in the unknown category, really.

Regards, RAB
Thanks for that.
I reduce the entrance when the bees aren't flying and then open it up when they are all flying. I am also feeding. Do I have to stop feeding when the Apiguard is in?

I have monitored the varroa drop and am getting about 20-25 per week.

I am in sunny Birmingham.

Leave the reducer in all day. If they get congested getting in and out you have a very strong colony, not a weak one. As RAB says, they aren't going to suffocate. Entrances can be reduced to a single bee width.

It is possible you have a low varroa count because of the break in brood rearing it sounds like your colony had. I have a colony which almost starved on Dartmoor in August - my stupid fault - and the queen stopped laying so there was no sealed brood for quite a while. I have now fed them and the queen is laying again strongly but the mite fall as a result of a varroa treatment is very low. A broodless period is a bit like a shook swarm I suppose in this respect, and knocks back the population significantly.

But don't take chances. I would recommend following the instructions for the Apiguard and treat twice, even if there seems to be some stuff left in the tray after the first treatment. After two weeks most of the fumes will have evaporated, even if there is some solid stuff left. With 80% or thereabouts of the varroa in sealed brood in a normal colony the first treatment has no effect on these mites so the second application is needed to catch them as the emerge.
National hive
OMF with insert tray in
Entrance block on smallest setting
Brood box
Empty super
Crown board with porter bee escapes in
Roof with wasps
The holes in the crown board are feeder holes. They should be blocked off except when they have a feeder over them.

There you are, same answer from three beekeepers :D