Welcome, Guest

Author Topic: scientific evidence for top entrance/vent  (Read 5250 times)

Offline derekm

  • Field Bee
  • ***
  • Posts: 536
scientific evidence for top entrance/vent
« on: November 13, 2012, 11:56:56 AM »
Can some one point me to reviewed papers published that investigate quantatively top vent/entrance versus bottom entrances
If they increased energy bill for your home by a factor of 4.5 would you consider that cruel? If so why are you doing that to your bees?

Offline BlueBee

  • Galactic Bee
  • ******
  • Posts: 4587
  • Gender: Male
Re: scientific evidence for top entrance/vent
« Reply #1 on: November 13, 2012, 02:19:33 PM »
And how about some papers about mid entrances too?




Offline Finski

  • Galactic Bee
  • ******
  • Posts: 3928
  • Gender: Male
Re: scientific evidence for top entrance/vent
« Reply #2 on: November 13, 2012, 02:31:57 PM »
.
That is a very good question.

We here in notrh, and many more north to me, would have much advantage if we would have researches about

what is proper ventilation

- mesh floor
- solid floor
- wind affections
- beginning of winter - late winter (brood)

.
Language barrier NOT included

Offline Jeanette

  • House Bee
  • **
  • Posts: 64
  • Gender: Female
Re: scientific evidence for top entrance/vent
« Reply #3 on: November 15, 2012, 09:00:30 PM »
Not sure if this is what you are looking for:

The Canadian Association of Professional Apiculturalists wrote paper about 'The Biology and Management of Colonies in Winter'. On page 3 they have a short summary and diagram about 'the amount of honey consumed (winter weight loss), spring adult populations and nosema levels among colonies with different types of entrances'.  Sorry, I couldn't find the original Alberta study online.

Quote from paper:
"The best way to vent extra moisture from wintering colonies is with an upper entrance. This entrance is very important! A study from northern Alberta, for example, demonstrated that either a 1 x 1.5 cm top entrance built into the inner cover or a 2.5 cm diameter hole in drilled into the middle of the upper brood box greatly increased colony strength, health and decreased the consumption of honey stores (Fig. 7)."

Figure 7 compares:
"1) bottom and top entrances 1 x 1.5 cm each,
2) bottom (1 x 1.5 cm) and top (2.5 cm dia in middle of 2nd chamber),
3) bottom and side (1 x 1.5 cm each) and
4) fully open bottom entrance and no top (from Szabo 1982)."

http://www.capabees.com/main/files/pdf/winteringpdf.pdf
« Last Edit: November 15, 2012, 09:10:42 PM by Robo »
Jeanette

Offline BlueBee

  • Galactic Bee
  • ******
  • Posts: 4587
  • Gender: Male
Re: scientific evidence for top entrance/vent
« Reply #4 on: November 16, 2012, 02:53:44 AM »
Jeanetta, thanks for that paper!  Some good points.

Certainly no reviewed papers coming from my little bee yard  :(  I have been wintering bees in polystyrene boxes with an assortment of entrances/vents to see what works and what doesn’t work in my climate.

After listening to Derekm’s thermal arguments for a bottom only entrance/vent (ie “heat bubble”) I decided to go that route in my latest generation of foam nucs.  I sure hope he’s right! :-D  Here’s a photo of my latest design.





From a physics perspective, Derekm should be correct.  These should be warmer than including a top vent or entrance.  For small colonies, I suspect that is a more important design attribute than for large full sized hives.  I’ve wintered my full sized foam hives with top entrances for a few years now with zero losses so far.  The large colonies stay pretty warm in my insulated hives even with a modest top entrance.

Offline Finski

  • Galactic Bee
  • ******
  • Posts: 3928
  • Gender: Male
Re: scientific evidence for top entrance/vent
« Reply #5 on: November 16, 2012, 05:05:36 AM »
.

It has been a disaster that Floridan and Californian beeks give wintering advices to Michigan and to Canada, and now you have a specialist from Uk, which hardly has seen snow on ground.

Good Lord......



 
.
Language barrier NOT included

Offline little john

  • House Bee
  • **
  • Posts: 119
Re: scientific evidence for top entrance/vent
« Reply #6 on: November 16, 2012, 05:34:40 AM »
Deleted - 'cause on second thoughts I've decided not to join in on this one ...
« Last Edit: November 16, 2012, 05:44:54 AM by little john »

Offline Robo

  • Technical
  • Administrator
  • Galactic Bee
  • *******
  • Posts: 6492
  • Gender: Male
  • Beekeep On!
    • Robo's World
Re: scientific evidence for top entrance/vent
« Reply #7 on: November 16, 2012, 07:31:49 AM »
After listening to Derekm’s thermal arguments for a bottom only entrance/vent (ie “heat bubble”) I decided to go that route in my latest generation of foam nucs.  I sure hope he’s right! :-D 

For what it is worth, I've tried many incantations over the years,  but currently for last 3-5 years I have settled on overwinter with no upper ventilation in polystyrene hive without issue.   My personal opinion is a lot of folks leave too much space for the bees.  Despite conventional wisdom of 2 deeps here in the NE,  I knock all mine down to just one.   With the added insulation of the polystyrene,  consumption is greatly reduced and they have plenty of stores to get through the winter.Also,  another key point that Finski often points out is that you want the highest insulation value in your cover so that condensation does not take place there.
 
Here are some pictures.  I do put a 2" shim on to allow for feeding of pollen patties or sugar if needed. 



Here are some from last February  when I did a check.



I have also had good success with poly 5 frame nucs with no ventilation as well.  I do have a 1/2" weep hole in the bottom to drain any condensation that forms on the wall and runs down. They usually spend a good portion of the winter buried in the snow.


"Opportunity is missed by most people because it comes dressed in overalls and looks like work." - Thomas Edison



Offline Finski

  • Galactic Bee
  • ******
  • Posts: 3928
  • Gender: Male
Re: scientific evidence for top entrance/vent
« Reply #8 on: November 16, 2012, 07:51:52 AM »
.
I have enough experience in wintering my hives.
Hives do not starve out and i do not give extra feeding after September.
My biggest concern in Spring is to get rid of the rest winter  food before when next summer gives honey.

Do better and better.  it goes enough this way and often this is boring after 50 years.


What I am interested  is better spring build up I know quite well how it goes.

If I would give water to them when they eate pollen patty, it surely gets better results but I must have life too outside those eternal hives.

I do not want either that hives are too much dependent on artificial systems which may collapse.

.it was interesting to see that when bees cannot get drinking water from soil, they did not eate patty. When they get it in the middle of day, it started again eating on afternoon.
Fist I thought that they did not like the patty formula.

Varroa and its viruses are bigger problem than insulation of hives. Ventilation and insulation is not a problem to me. I continue this way.



 
.
Language barrier NOT included

Offline BlueBee

  • Galactic Bee
  • ******
  • Posts: 4587
  • Gender: Male
Re: scientific evidence for top entrance/vent
« Reply #9 on: November 16, 2012, 03:22:15 PM »
99% per of my new Gen 4 foam nucs are single stories, but this one is a double decker in the back yard.  This photo shows the plastic sheet/inner cover I’m using on these hives.  The foam top is setting next to the hive, bottom down.  Note:  it is telescoping to ensure rain doesn’t drip into the nucs.



As you can see, the bees have propolized the plastic sheet to the top of the hive to prevent any air infiltration.  When I then put the foam cover on that, the plastic makes for a nice insulating gasket so there should be no air leaks at the top of the hive. 



The nice thing about these plastic inner covers is I can finally watch what goes on inside the hive during the winter.  The darker ares on the bottom of photo are bees; lots of bees  X:X X:X X:X X:X



Offline saperica

  • House Bee
  • **
  • Posts: 61
  • Gender: Male
Re: scientific evidence for top entrance/vent
« Reply #10 on: November 16, 2012, 03:37:41 PM »
bluebee thanks for photos and for the information about  using a hdps for making a nucs, and pe foil for cover of hive like in germany.
nice jobs.

Offline BlueBee

  • Galactic Bee
  • ******
  • Posts: 4587
  • Gender: Male
Re: scientific evidence for top entrance/vent
« Reply #11 on: November 16, 2012, 03:47:31 PM »
Yeah, I stole....I mean borrowed  :-D.... that plastic inner cover idea from some German video I saw.  Those Europeans have some good ideas! 

Offline Robo

  • Technical
  • Administrator
  • Galactic Bee
  • *******
  • Posts: 6492
  • Gender: Male
  • Beekeep On!
    • Robo's World
Re: scientific evidence for top entrance/vent
« Reply #12 on: November 16, 2012, 05:54:53 PM »
I don't have any pictures,  but I build a few 2" blue insulation nucs this year and I glued pieces of the silver emergency blanket to the bottom side of the cover.   Creates the same seal, and perhaps reflects some heat back down to the bees as well.   I guess I'll see how it works.
"Opportunity is missed by most people because it comes dressed in overalls and looks like work." - Thomas Edison



Offline Finski

  • Galactic Bee
  • ******
  • Posts: 3928
  • Gender: Male
Re: scientific evidence for top entrance/vent
« Reply #13 on: November 16, 2012, 06:01:36 PM »
.
Are we inventing a wheel again?
And who needs it?

Scientific hole...
.
Language barrier NOT included

Offline T Beek

  • Super Bee
  • *****
  • Posts: 2775
  • Gender: Male
Re: scientific evidence for top entrance/vent
« Reply #14 on: November 17, 2012, 11:21:09 AM »
Excellent thread, thanks everyone!

As usual, great PICS!

What a difference a day makes.

On Tuesday the 13th my wife and I placed 1" foam around all of our 8 colonies.  On Wednesday w/ temps approaching the high 40's we had bees congregating around the entrances and flying who knows where.  This ONE experience has convinced me of poly/foams value even more.
"Trust those who seek the truth, doubt those who say they've found it."

Offline little john

  • House Bee
  • **
  • Posts: 119
Re: scientific evidence for top entrance/vent
« Reply #15 on: November 19, 2012, 06:08:54 AM »
The nice thing about these plastic inner covers is I can finally watch what goes on inside the hive during the winter.  The darker ares on the bottom of photo are bees; lots of bees  X:X X:X X:X X:X




Great pictures !

Seeing those attempts to seal against the plastic reinforces my firm conviction that having any kind of space above the combs is fundamentally undesirable.
As David Heaf has astutely commented: "[In the feral nest] Round the tops and edges of the combs there is no bee space. Bee space was an invention, not a discovery, by Rev. L L Langstroth, for the convenience of the beekeeper." The Welsh Beekeeper, Winter 2011, p.14

Ok - so it's hard to imagine framed hives without having anti-propolising gaps between each box - but in long hives and the topmost box of stacked arrays, it would seem that not having a top bee-space would lend itself more readily to covering the frames with a sheet of plastic, thus enabling the bees to more easily seal their inter-comb cavities - as they are so wont to do.

LJ

Offline derekm

  • Field Bee
  • ***
  • Posts: 536
Re: scientific evidence for top entrance/vent
« Reply #16 on: November 19, 2012, 09:43:28 AM »
So no one has a set of results comparing top entrance/vent with bottom only. Thats disappointment   My own quantitive experiments have led me to seal the outside box and  roof  joints  of our hives  with cling film/saran wrap. I would like to see some other research on this, for or against.
If they increased energy bill for your home by a factor of 4.5 would you consider that cruel? If so why are you doing that to your bees?

Offline Finski

  • Galactic Bee
  • ******
  • Posts: 3928
  • Gender: Male
Re: scientific evidence for top entrance/vent
« Reply #17 on: November 19, 2012, 09:57:45 AM »
.
I do not need science in my hives to see how bees react if I keep the upper entrance open or it is closed.

For example if i have in summer flow 4 medium supers and 3 langstroth deeps, my main entrance is widely open andthen I have 2 hole open in deeps. Super openings are all shut.

I look from number of ventilating bees, is that enough.

If I open more holes, the hive is cold and the queen tend to rise up to supers.

There are hot weeks and cold weeks and I do not run to open and close holes according the weather.

The importance of upper hole in winter I found it 45 years ago and since that it has been open.

If some say that I need not upper hole, thank you but I use it.
What ever the science says, I use it. And what ever guys say about mesh floor, I do not use it.

So simple.

.
.
Language barrier NOT included

Offline derekm

  • Field Bee
  • ***
  • Posts: 536
Re: scientific evidence for top entrance/vent
« Reply #18 on: November 19, 2012, 12:06:50 PM »
.
I do not need science in my hives to see how bees react if I keep the upper entrance open or it is closed.

For example if i have in summer flow 4 medium supers and 3 langstroth deeps, my main entrance is widely open andthen I have 2 hole open in deeps. Super openings are all shut.

I look from number of ventilating bees, is that enough.

If I open more holes, the hive is cold and the queen tend to rise up to supers.

There are hot weeks and cold weeks and I do not run to open and close holes according the weather.

The importance of upper hole in winter I found it 45 years ago and since that it has been open.

If some say that I need not upper hole, thank you but I use it.
What ever the science says, I use it. And what ever guys say about mesh floor, I do not use it.

So simple.

.

but what problem is that upper hole supposed to fix?
If they increased energy bill for your home by a factor of 4.5 would you consider that cruel? If so why are you doing that to your bees?

Offline little john

  • House Bee
  • **
  • Posts: 119
Re: scientific evidence for top entrance/vent
« Reply #19 on: November 19, 2012, 04:22:34 PM »
The importance of upper hole in winter I found it 45 years ago and since that it has been open.

If some say that I need not upper hole, thank you but I use it.


Isn't there a little bit of inconsistency here ... ?

From the "We in USA .....need not insulation" thread:
Quote
Reply #22 "Finski"
I must try that match stick method. I am eager to measure how fast the hive looses its winter stores. I bet that in 2 months.

But a hole is a hole is a hole - whether made by a tool, or created by a matchstick. In one thread you appear to ridicule the idea of top ventilation, yet in another you support the idea.

LJ (confused)


 

anything