Snow shrinkback from polys

[Finman]

.
Hivemaker's test is smart. Bees need a proper ventilation, not more. The more makes harm.

Mesh floor came to Britain 20 years ago. How bees had survived before that all those centuries?

In Finland mesh floors are closed with plate to avoid wind. Many keep them open but it makes no sence. it is religion like issue.

In nature bees try to make the entrance smaller before winter with resins. Caucasian bee is good in that job.

 

[hedgerow pete]

i must admit that i am old school and have only this year gone to mesh floors but that was because i was getting to high humidity in the shed,

i much prefere solid floors .

the other thing i seem to try and do that is going out the window is leaving the bees alone over the winter time, some times reading the forum some beeks still seam to be doing inspections and hive fiddlings.

i was all ways told that when its cold there are better off being left alone as they have there own little routine going and mucking them about just seams to make matters worse, if they have enough stores they should come through the winter ok.

is it just me or does other beeks think the same , has the winter solace been broken and do modern beeks seem to do to much bee keepering over the winter??

 

[Finman]

.
I have fast bottoms. During main yield i keep the entrance wide open. After yield season i restrict the entrance 70%. I have learned that when I have looked the amount of ventilating bees and the habit how bees make brood area. - to keep the whole bottom open, it feels really odd.

In spring I want fast build up and in late summer I want large brood are for winterbees.

Simple flat box is not a good botton. Hivemaker have forwards slanting bottoms. I have construction which lead water from bottom. Hive is not water tight. I have small holes in back corners of bottom. It makes a litte draft and keep back stage dry.

Small nucs are most sensitive to cold. I keep finger size entrance in them. Some keep mesh floor open. Is it a strance difference beween these 2 methods?

 

[Monsieur Abeille]

is it just me or does other beeks think the same , has the winter solace been broken and do modern beeks seem to do to much bee keepering over the winter??

Pete - even as a overly concerned newbeek I agree with you, there does seem to be a lot of unessesary fiddling going on. As someone (RAB?) suggested, if they are dead there is nothing you can do about it, why fuss. Someone else (HM?) suggested that after whacking the side of a hive to get a reaction it takes them 24 hours to settle back down. Can't be good.

We all want our bees to have the best chance of survival, and to me that means leaving them alone until spring apart from possibly a very occasional food check (which needn't disturb them)

 

[the naked beekeeper]

Thought i would just do an experiment to check on heat loss via a mesh floor, compared to solid. Athough only with bulbs,i intend to do another with full colonys,will be interesting to see the variation in this as well,and to see how much warm air gets sucked out the bottom by the wind.

Two new,near identical cedar hives,roofs with no vents,crown boards with open feed hole,brood boxs,frames,some empty, some full but equal,and one with a solid floor,one with open mesh.

Two hives are stood side by side on a 10" stand,with a pair of accurate matched thermometers, placed in the same position on top of each crown board,and a large fan placed a few ft in front,and central to both hives to simulate a light wind.
Inside in the center of each hive is a 150 watt bulb to act as heat source.

After 1 hour with fan facing entrance on hive with mesh floor the temp is 17c

After 1 hour with fan facing entrance on hive with solid floor the temp is 29c

Another hour but with hives turned so wind direction would be from rear,

open mesh 17c
solid.. 26c

That is very interesting, but what do we conclude??

In the Winter, it may well be more beneficial to have a lower temperature in the hive, as this would induce the bees to cluster more and conserve stores, whereas a more ambient temperature would mean they walk around using stores, which they cannot replace.

However, in Spring, for build up, we would want a higher ambient temperature, and to reduce the effects of wind/draught.

Perhaps there is a case for OMF in the Winter and Closed floor in the Spring-Autumn. Keep the bees clustered for Winter, but active when there is opportunity to build up. Best of both worlds.

 

[Finman]

That is very interesting, but what do we conclude??

In the Winter, it may well be more beneficial to have a lower temperature in the hive, as this would induce the bees to cluster more and conserve stores, whereas a more ambient temperature would mean they walk around using stores, which they cannot replace.

what we conclude is that wind blows the heat away and bees must eate more to keep warm themselves.

Beehive' duty is to give a shelter to the colony, not to keep them cool.
So bees can regulate the cluster temperature.

I looked Corwall's forecast. Day temp 9 and night 3.
It is February and I bet that hives have some brood now.
.

In Helsinki we have -17C and in Kuusamo -37C.
A border guard just tells with phone that they are in a river valley and their
meter shows -43C. "So much cold that we could sell it"
.

 

[oliver90owner]

crown boards with open feed hole,

Run the test again with proper crownboards and maybe a far lower wattage bulb?

I agree with Finman that they will need more food to maintain the temperature, but the heat exchange where the delta T's are much reduced and with the bees in a cluster, that difference in energy required will not be anywhere near as obvious as in your test.

As an aside, were the roofs fitted in the same orientation? Did you theck your results by changing the floors between the hives and with changing the boxes from one position to the other?

You have some very raw data from what appears to be a simple arrangement. You have the result, I would have expected. It is just that there may be other variables affecting the results, if the tests were carried out very simplistically.


I might conclude all manner of things, one being that an air flow across a mesh floor may induce a higher convection flow through that hive. I would be wrong to come to that conclusion, on the limited information to hand, so I think it needs more investigation.

RAB

 

[OXFORDBEE]

Thought i would just do an experiment to check on heat loss via a mesh floor, compared to solid. Athough only with bulbs,i intend to do another with full colonys,will be interesting to see the variation in this as well,and to see how much warm air gets sucked out the bottom by the wind.

Two new,near identical cedar hives,roofs with no vents,crown boards with open feed hole,brood boxs,frames,some empty, some full but equal,and one with a solid floor,one with open mesh.

Two hives are stood side by side on a 10" stand,with a pair of accurate matched thermometers, placed in the same position on top of each crown board,and a large fan placed a few ft in front,and central to both hives to simulate a light wind.
Inside in the center of each hive is a 150 watt bulb to act as heat source.

After 1 hour with fan facing entrance on hive with mesh floor the temp is 17c

After 1 hour with fan facing entrance on hive with solid floor the temp is 29c

Another hour but with hives turned so wind direction would be from rear,

open mesh 17c
solid.. 26c

Interesting, I wonder what the impact of open mesh floors is on spring development..

 

[drstitson]

very interesting and would justify a write up in beecraft IMHO (but only if you run a batch using matchsticks - seriously!).

suggestions:

repeat with several different bulb wattages.
repeat with solid crownboards.
repeat without airflow.
repeat exactly as before but with the hives switched.
perhaps repeat with airflow but with an empty super under the floor to remove direct interface between airflow and mesh.

might also be nice to work out what wattage Finman's head puts out when reading about UK winter beekeeping practices!!!!!

 

[OXFORDBEE]

Matchsticks and different roof lengths would be interesting too. Use roofs of 4", 6" and 12" depth. I bet even though the crownboard is raised on a matchstick the 6" and 12" roofs might yield an interesting result.

 

[drstitson]

forgot to include in my list +/- 50mm kingspan/celotex.

 

[region2]

So on windy days install the varroa floor with the OMF?

R2

 

[drstitson]

here's an idea - small windmill on top of hive attached to a pulley system in the floor which draws the monitoring board (sprung to keep it out otherwise) in to cover the mesh.

 

[user 6228]

Thought i would just do an experiment to check on heat loss via a mesh floor, compared to solid. Athough only with bulbs,i intend to do another with full colonys,will be interesting to see the variation in this as well,and to see how much warm air gets sucked out the bottom by the wind.

Two new,near identical cedar hives,roofs with no vents,crown boards with open feed hole,brood boxs,frames,some empty, some full but equal,and one with a solid floor,one with open mesh.

Two hives are stood side by side on a 10" stand,with a pair of accurate matched thermometers, placed in the same position on top of each crown board,and a large fan placed a few ft in front,and central to both hives to simulate a light wind.
Inside in the center of each hive is a 150 watt bulb to act as heat source.

After 1 hour with fan facing entrance on hive with mesh floor the temp is 17c

After 1 hour with fan facing entrance on hive with solid floor the temp is 29c

Another hour but with hives turned so wind direction would be from rear,

open mesh 17c
solid.. 26c

floor and entrance design is significant even in still air... however you should try this with a wattage that is closer to a bee colony i.e 20W.

I have done side by side experiments with a PIR nuc along side a cedar hive As would be predicted 20w has difficulty even closed floor to give a 4C temp difference half way up the hive after several hours.
The PIR nuc gave 25C on only 5 W

 

[Monsieur Abeille]

Do you leave the feeders on all winter? Is this for fondant?

ITLD uses this method, was thinking of trying it myself next winter if I can find a suitable bottom bee space national size poly feeder

 

[Poly Hive]

I have mine on now covering the fondant. The CB covers the access hole and keeps in the warmth. Bees are fine. There are no beespace issues as they are used upside down for fondant.

PH

 

[Hivemaker.]

here's an idea - small windmill on top of hive attached to a pulley system in the floor which draws the monitoring board (sprung to keep it out otherwise) in to cover the mesh.

Thats a good idea,will leave that design feature to you doc,would keep the peckers away as well.

Looking at the heat loss from the floors of the poly hives,i think i will just stick to the solid floors, and much less heat loss.

 

[user 6228]

Thats a good idea,will leave that design feature to you doc,would keep the peckers away as well.

Looking at the heat loss from the floors of the poly hives,i think i will just stick to the solid floors, and much less heat loss.

It is possible to not have a solid floor(allowing varrroa and wax to fall to the ground )

and the floor be 20C above ambient on the heat from the bees of a smallish colony (e.g.today)
and with the entrance open 20 cm2....

but then my hives are heretical and so are my bees

 

[Teemore]

Some (but not all) of the shrink back of snow around the poly hives will be from water dripping off the roof.

My Inspection floors have been firmly in place since I used OA between Christmas and New Year: they will stay in place until mid march approximately (weather dependant).

Going off on a slight tangent, do comparable colonies start swarm preparations sooner on OMFs or on solid floors?

 

[Skyhook]

crown boards with open feed hole,

Run the test again with proper crownboards and maybe a far lower wattage bulb?

RAB

Brilliant idea for experiment, but it would be more valuable with some of the variables changed. I'ts been said lots of times on here that OMF plus top ventilatiion is BAD due to chimney effect.

It would be very interesting to try a proper set-up of OMF plus insulated crown board, much smaller bulbs, and temperature measured inside the hive, against the same but with solid floor.

If only I had 2 empty hives, I'd be tempted to join in!