Giving a talk on Poly Hives - Need evidence

[Poly Hive]

another hits ignore.

PH

 

[Finman]

another hits ignore.

PH

Yeah, the Giant of Humour

 

[user 6228]

Nope and frankly cannot see why you need them.


PH

Well you could actually make a informed decision about which is the warmer hive type to purchase, even to decide between poly hive makes, based on objective measurement rather than subjective opinion. theuy even do that with washing machines

...

Further there is no one in the UK to do such work now.
...

PH

Perhaps no one is being paid but its really only GSCE science combined with undergrad level methodology...

and being physics rather than animal behaviour the repeatablility is very good and the error analysis much simpler.

 

[Poly Hive]

Err yes but a reasonable sample is needed.

I am no scientist, but I would have thought 50 would be a min?

PH

 

[Into the lions den]

Well you could actually make a informed decision about which is the warmer hive type to purchase, even to decide between poly hive makes, based on objective measurement rather than subjective opinion. theuy even do that with washing machines

Its pretty simple. The insulation value is directly proportional to the thickness, and inversely proportional to the density. The data is out there and easy to find if one can be bothered.

Density is the big one. Light poly is warmest for the same thickness, but also less durable and below 80g/litre the bees chew holes in it. 100g to 120g is the best compromise. Thermal conductivity tests at various densities have been done.

 

[user 6228]

Its pretty simple. The insulation value is directly proportional to the thickness, and inversely proportional to the density. The data is out there and easy to find if one can be bothered.

Density is the big one. Light poly is warmest for the same thickness, but also less durable and below 80g/litre the bees chew holes in it. 100g to 120g is the best compromise. Thermal conductivity tests at various densities have been done.

s
its not quite as straight forward as that... there's that hole in the bottom... so theres not only conduction but also mass movement.
and hive designs are not uniform thickness ...

just using the solid conductance values of the poly material and the box surface area gives a substantial error.

 

[Into the lions den]

s
its not quite as straight forward as that... there's that hole in the bottom... so theres not only conduction but also mass movement.
and hive designs are not uniform thickness ...

just using the solid conductance values of the poly material and the box surface area gives a substantial error.

Of course they are not uniform thickness, some are actually remarkably thin at certain places.

However, the basics of solid conductance are the most important. The rest is down to beekeeper/weather introduced variables.

Even our thickest roofs have a heat transfer issue going on as is plainly visible when snow lies on the tops. Easy to spot the dead or poorly ones in a couple days, though much more quickly in the wooden ones, as the snow melts first over the warm clusters.

 

[Elaine]

Err yes but a reasonable sample is needed.

I am no scientist, but I would have thought 50 would be a min?

PH

Large sample sizes are only needed when working with variable 'subjects'. As this study is dealing with 'standard' hives - where the manufacturing tolerances ensure uniformity, this is not required. This is why the tree nest model, the amount of food taken by bees over winter, and the temperatures at which they cluster etc, have all been taken from published research, which will have a significant sample size, rather than figures taken from our own 4 colonies.

 

[Finman]

If we ask this what the question: what evidencies you have that national hive is good?

So, how wise is the question about polyhive evidencies.

 

[Elaine]

If we ask this what the question: what evidencies you have that national hive is good?

So, how wise is the question about polyhive evidencies.

The National hive may or may not be the best size - _but_ the comparrision with a National sized poly hive, or National size home-made hive is still a valid measurement. It could equally be done using different types of hives, the results are still a valid comparision of the amount of energy needed to maintain a certain temperature inside.

 

[Into the lions den]

The National hive may or may not be the best size - _but_ the comparrision with a National sized poly hive, or National size home-made hive is still a valid measurement. It could equally be done using different types of hives, the results are still a valid comparision of the amount of energy needed to maintain a certain temperature inside.

I am not that worried about the exactitudes of this stuff. Bottom line is that we have half the winter losses in poly compared to wood of the same size (Langstroth), and production runs between 20 and 30% ahead per colony. That is over hundreds of colonies and a 15 year line of experience. Only ONE year did they fail to make the minimum of 20% better performance.

If asked about the difference between the hive types in a simple statement.....'In wooden hives we often have trouble keeping our numbers up...........in poly hives we have trouble keeping our numbers down.'

Other than some replacement to keep the unit working, have no intention of ever buying wooden hives again. All new units will be poly.

 

[Finman]

It could equally be done using different types of hives, the results are still a valid comparision of the amount of energy needed to maintain a certain temperature inside.

Right Elaine

folks have many kinds of hives.

Like in the picture the hives are propably thin ply. Then there is 5 cm insulation gap, what ever material it is. Some constructions are light.

My opinion is that polyhive has low price compared to self made insulated hive. Our all wintering hives are insulated. Supers and summer boxes may be what ever.

Last I bought 50 used polyboxes and price was 7 euros.


If we look honey yield, it depends on flower pastures and distanges how far bees fly.

.
Hive must bee handy to beekeeper.
.

 

[Finman]

If asked about the difference between the hive types in a simple statement.....'In wooden hives we often have trouble keeping our numbers up...........in poly hives we have trouble keeping our numbers down.'

.

That has been my problem since I started to mate queens in 3-frame polynucs.
In Autumn I have so much extra brood frames that i do not know what to do with them

When I started to bye polyboxes, the price was really high. But they brought so much honey that I got the money back in first year.

 

[user 6228]

If we ask this what the question: what evidencies you have that national hive is good?

So, how wise is the question about polyhive evidencies.

national was only used because it what we had, and we had 3 versions to compare... As the research progresses we will have more than one hive type as it is possible (perhaps definitley) that the national has its own thermal idiosyncrasies.

This research is confined to the physical properties of the hive and we have the skills and cpabilities to make a full error analysis on the physical properties. While we can and will make observations about how our 4 colonies react to a different thermal environment compared to most hives, we cant at present conduct statisitically significant experiments on how bees react to tree nest levels of insulation. One can speculate that the bees know what do when confronted with such circumstances but what will they will do ?

 

[Black Comb]

Does anyone mix poly brood boxes with wooden supers? (Top bee space)

 

[user 6228]

Does anyone mix poly brood boxes with wooden supers? (Top bee space)

have done this in emergency when the kit runs out as it does ... but thermally its a no no!.
Remember the bees need a lot of heat(energy) to ripen the honey. Heat losses at the top of hive will make this more difficult.

 

[tonybloke]

Does anyone mix poly brood boxes with wooden supers? (Top bee space)

I would if I could find poly's in a 16x10 format

 

[drstitson]

always best to have one poly super per hive to help in early season. after than wood is fine.

 

[oliver90owner]

Does anyone mix poly brood boxes with wooden supers? (Top bee space)

Of course! First (early) super was poly, but then timber.

Any suggestion that it is a no, no, needs to think about the circumatances. In a normal spring and summer (NOT like this year!) the second and subsequent boxes will be added in warmer weather. Further the brood will, by then, be full of bees; they will be able to regulate the brood nest temperatures easily and the thermal plusses and minuses are relatively trivial. After all there are still lots out there that leave gaping holes in the crown board anyway.

 

[Finman]

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I have wooden boxes for 20 hives what I made 1966. I use them as supers. They are like new. But they are heavy. Wood is scotch pine.