Crown boards and ventilation ...

[Little John]

It seemed to me that the solid crown board versus upper ventilation argument would continue to run and run without agreement: the fashion with some on this forum seeming to lean towards the former, whilst those who keep Warre hives favouring the latter with the installation of porous quilts - and so I decided that rather than engage in further fruitless arguments, it was about time someone actually 'asked the bees' by running a simple experiment which offered bees a choice between them.

I have built a crown board for a Warre Hive (fitted with an OMF) with one central hole to accomodate a feeder, and 4 ventilation slots positioned towards the periphery - each slot being approximately 100mm x 5mm. These slots vent to the outside world via channels which pass through the feeder box. Two of these 'pass-through' channels have flow moderators (screwed-up windbreak netting) installed, and two remain empty to maximise the air-flow through them.
In order to prevent insects such as spiders from nesting in the slots, expanded aluminium mesh is fitted to their exits, and to prevent bees from entering these ventilation slots, fine plastic mesh is attached to the under surface of the crown board - thus providing the bees with the facility of propolising over the fine plastic mesh to seal the crown board if they so wish, or leave the slots open to continue to provide a modest amount of ventilation.

In the several months that this experiment has been running, the bees have propolised the crown board to the box under it, and the lugs of the Delon frames to the box rebates. But they have yet to propolise either those slots with moderated air-flow, or those providing a somewhat greater amount of ventilation.
As autumn moves toward winter, it will be interesting to see whether the bees decide to regulate upward air movement within their hive by propolising shut one or more of these ventilation slots.

LJ

 

[user 6228]

|I have done this experiment twice on my insulated hives. They rapidly propolised the mesh in both cases

 

[oliver90owner]

porous quilts

Just about says all it needs to. With a porous quilt the air flow is minimal, it allowing water vapour to exit under very steady condition all through the winter. The bees would likely propolise the cover, just as they do the rest of the hive interior. Again, any thing layer of propolis would allow some transfer of gases including the water vapour, but l very much doubt they need that gas exchange for survival for metabolism and it simply serves as a medium for transferring water vapour to the fabric of the hive, the natural warmth of the hive preventing it remaining and getting sodden. I wonder how much water a Warre quilt absorbs over the winter? Quite a bit, Iwould think, but I am not going to even bother to investigate.

The amount of gaseous flow may be very minimal in this experiment and the cluster might well move to the warmer side - who knows! I do know the bees do move to a warmer side, as experienced when one sheet of side insulation slipping, on a Dartington, led to that complete half of the brood frames being left full of stores at spring! Yes, about eight half frames of brood (perhaps a little more) and the rest stores with me unable to remove any stores to make brooding space - laying in a shallow above, that year, very early in the seaon!

So, I doubt this will show anything other than what the poster wants to see or thinks has happened. One swallow does not make a summer and one quilt on one hive will be about as good as the saying, I reckon.

Matchsticks are out with OMF. Top ventilation is not needed, where heat energy will be lost to the colony, and the hive remains dry. OMFs afford far more bottom ventilation than required (see John Harding's book for that. Bees can survive outside all through the winter and in no pictures I have ever seen has there been a hole, out to the atmosphere, at the top of the combs. ALWAYS sealed at the top.ALWAYS.

 

[Little John]

Predictable responses of course, by those who advocate one particular methodology.

I find it offensive for someone to suggest that I expect particular results - this 'back-of-a-fag-packet' experiment will show what it will show - and of course it's only one experiment on one hive, that is self-evident - but then, this type of response has been par for the course on this forum for some time.

No propolised vents so far - but we shall wait and see - without bias or prejudice.

LJ

 

[TryingToLetThemBee]

I read an American's site where he talked about CO2 levels being a swarming signal so he top-vents in spring/summer to build mega-colonies and help ripen honey. Made sense to me but I didn't want to spring for the ebook to get all the deets.

 

[madasafish]

I read an American's site where he talked about CO2 levels being a swarming signal so he top-vents in spring/summer to build mega-colonies and help ripen honey. Made sense to me but I didn't want to spring for the ebook to get all the deets.

And where was he living? Florida or somewhere warmer?

The USA is rather large and has a huge climatic range.

 

[TryingToLetThemBee]

Much less so in summer. I'll see if I can dig it out.

 

[TryingToLetThemBee]

And where was he living? Florida or somewhere warmer?



The USA is rather large and has a huge climatic range.

Miles Stair. Oregon. http://www.endtimesreport.com/Beekeeping.htm

 

[user 6228]

Predictable responses of course, by those who advocate one particular methodology.

I find it offensive for someone to suggest that I expect particular results - this 'back-of-a-fag-packet' experiment will show what it will show - and of course it's only one experiment on one hive, that is self-evident - but then, this type of response has been par for the course on this forum for some time.

No propolised vents so far - but we shall wait and see - without bias or prejudice.

LJ

in my case i had invested considerable effort in providing mesh screened (2mm 50% mesh) vents. I had had plans to make thermostatically controlled versions of these vents.
All that went out the window when the bees coated them over. I remember seeing the water vapour condensing outside the vent and forming droplets. On looking underneath the mesh was covered with bees propolising.


My 2 experiments on bees reacting to vents are insufficent for a study of animal behaviour, particularly a set of behaviour as complex as honeybees. I would suggest that any results of your own based on only one or two hives will be similarly insufficient.
That I can get two contradictory results doesnt prove you wrong but at least says you need to do much more detailed and extensive work to reach any meaningful conclusion

I like physics experiments as you only have to repeat the measurements a few times and get a nice tight standard deviation number, then combining that with the behavioral research of others. Animal behaviour research needs much more careful statisitics than just Standard deviation.

My advocacy of insulation is based on research, experimentation, and hard science. I find it offensive that others hint my research is biased and my results fixed before i make the experiment

 

[madasafish]

It's an interesting idea. I would have thought with our variable weather and the different types of bees around, you might get a statistically meaningful answer after three decades worth of data from several hundred hives in several locations in the UK.

Otherwise any answer my be localised to both the type of bee and your location...

getting funding may be an issue...

 

[user 6228]

I read an American's site where he talked about CO2 levels being a swarming signal so he top-vents in spring/summer to build mega-colonies and help ripen honey. Made sense to me but I didn't want to spring for the ebook to get all the deets.

The latest research http://www.sciencedaily.com/releases/2014/08/140820091609.htm
seems to indicate that its only a theory amongst others as to how bees can tell how big the colony is.
However, disturbing the signals the bees may use, can have unforeseen circumstances.
e.g. a possibilty: stress the colony to increase colony size which then may increase to susceptablility to disease

 

[BeeJayBee]

I read an American's site where he talked about CO2 levels being a swarming signal so he top-vents in spring/summer to build mega-colonies and help ripen honey. Made sense to me but I didn't want to spring for the ebook to get all the deets.

I think, from the article, this person uses solid floors. A lot of US beekeepers give their colonies an additional upper entrance during the summer, and a lot drill holes in their boxes to give additional ventilation. I can't say it would be a good thing to do here in Britain, although I have heard of new beekeepers being told to make extra holes in the crown boards to enhance winter ventilation, even with open mesh floors.

As autumn moves toward winter, it will be interesting to see whether the bees decide to regulate upward air movement within their hive by propolising shut one or more of these ventilation slots.

I'm an advocate of good insulation and closed crown boards along with open mesh floors - because those are the floors I use. I can't see that they need any more ventilation, because bees are more than capable of moving air around the inside of their box if they want to. I've found that most colonies make good use of the brood box, often with brood on the outer face of the outermost frame - that's the one against the wall of the brood box - which, as far as I know, they don't in any standard wooden hive.

Some people compare bees choosing to live in a chimney with giving 'good' top ventilation in a hive, but they seem to forget that heat rises, and does the same upwards through a properly vented chimney or flue, even one that's out of use. It's also quite rare for the bees to build actually in a chimney pot.

Out of interest, what floors are you using LJ?

 

[Hivemaker.]

often with brood on the outer face of the outermost frame - that's the one against the wall of the brood box - which, as far as I know, they don't in any standard wooden hive.

Well they do here in wooden hives, so that's another myth.

 

[madasafish]

I winter here with closed roofs, insulation, OMFs and bottom boards. Lots of ventilation due to the wind.

Open floored TBHs in our local climate are a recipe for killing colonies: it's not the wind but the rain and damp...

 

[jenkinsbrynmair]

Well they do here in wooden hives, so that's another myth.

Theo only thing I find in a lot of my brood boxes mid summer is brood - every available cell, right up to the outer face of the far outer frames.
Wooden hives, OMF and no top ventilation

 

[BeeJayBee]

Well they do here in wooden hives, so that's another myth.

Theo only thing I find in a lot of my brood boxes mid summer is brood - every available cell, right up to the outer face of the far outer frames.
Wooden hives, OMF and no top ventilation

I stand corrected, thanks. My only excuse for ignorance is that almost all the wooden hives I know of have a lot of top ventilation, and I've never seen one with brood on the outer face of outer frames.

 

[jenkinsbrynmair]

I stand corrected, thanks. My only excuse for ignorance is that almost all the wooden hives I know of have a lot of top ventilation, and I've never seen one with brood on the outer face of outer frames.

I'm saying Porthcawl