# Is there a consensus on Screened bottom boards ?



## Mr.Beeman (May 19, 2012)

Always ran solid bottom boards with good ventillation from entrance to inner cover. That's all I can offer at this time. 
Feral hives don't have screened bottom boards though and the ones I remove seem to be doing just fine.


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## GaSteve (Apr 28, 2004)

I read the thread title and had to chuckle "Is there a consensus...". I think the consensus is there is never a consensus on anything in beekeeping.

SBBs were all the rage for a while but enthusiasm for them seems to have waned a bit. Some never liked them. I have seen hives try to propolize the bottom screen and/or the entire hive entrance which I take as them trying to correct for too much ventilation. IMO I'm sure a few mites drop through the screen, but not enough for any kind of significant control.


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## Andrew Dewey (Aug 23, 2005)

Consensus? No way. I'm near the coast and worry about the moisture from fog. But I know people inland from me who swear by sbb.


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## Acebird (Mar 17, 2011)

Andrew Dewey said:


> Consensus? No way.


Yeah, there is almost no consensus with anything beekeeping.

I like SBB because you can see the debris fall from the hive without opening it and it assures ventilation. If left open during the winter where I am the bees will not raise brood in the bottom medium box so this should be accounted for when setting up the hive for overwintering.


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## BadBeeKeeper (Jan 24, 2015)

I run screens for Summer, swap to solids for Winter- I don't particularly care to test their cold tolerance at -25 with a stiff wind. Sounds like a pain in the wazoo to swap them, but if you're rotating brood chambers anyway, it's no big deal.


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## shinbone (Jul 5, 2011)

I run screened BB in all my dozen-odd hives. The pull-out board is a quick, non-invasive and easy way to get a read on the hive's mite condition. If I need a more accurate mite number, I can always do an alcohol wash, but usually reading the pull-out board is good enough.

Our high altitude Sun is brutally intense during the peak of Summer in my area, and my hives sit in full sun all day. The extra ventilation the screened BB offers in the July and August is a good thing. Especially because the extra ventilation doesn't come at the expense of exposing the hive to robbing with a wide-open entrance.


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## David LaFerney (Jan 14, 2009)

staple a piece of window screen to the bottom of your sbb and it will catch and kill a surprising number of SHB larva trying to exit the hive. IPM for hive beetles.

I use both, and I'm absolutely sure that hives with solid bottoms send out more foragers on fair mid winter days.

But I don't even really have a consensus with myself.


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## Rader Sidetrack (Nov 30, 2011)

A constant flow of air in hot weather through an open screened bottom may work against the bees own efforts at keeping the hive cool via evaporative cooling with water that the foragers collect.

From the USDA Agricultural Research Service ....


> Bees store their food and raise their young in the honeycomb nest. Honeycomb is made from beeswax, which is secreted by young worker bees, and fashioned into the familiar honeycomb hexagonal shape. Because bees live in these wax combs, though, they have to keep the nest at a constant temperature, not only to keep the colony from overheating, but also to prevent the wax from melting. [HIGHLIGHT]In hot weather, bees cool the colony much like your swamp or evaporative cooler does - by evaporating off drops of water. Bees collect water and spread it throughout the colony in droplets. Then they fan the air to create an air stream over the water drops, causing the water to evaporate and thus lowering the nest temperatures.[/HIGHLIGHT]
> 
> http://www.ars.usda.gov/research/docs.htm?docid=11067&page=7


Evaporative cooling (swamp coolers) are likely to be less effective when they are not working within a relatively closed airspace.

One option to utilize a screened bottom is to use one that has an oil tray below the screen (to kill pest that fall through the screen), but has a solid bottom beneath the oil tray to block airflow.

.


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## NeilV (Nov 18, 2006)

The Bee Informed Survey people collected data on the percentages of hives surviving winter using screens vs. solids. Basically, no meaningful difference between them in hive survivability over winter. However, I would like to see more detailed analysis of that data. What I really want to see is an analysis of whether people using solid bottoms vs. screened ones tend to be migratory beekeepers and/or treat their bees. It could be that if commercial beeks who treat also tend to use one type of bottom, then the effect of the type of bottom board is getting lost in the analysis. (Believe it or not, commercial beeks who move their bees and treat reported lower, not higher, overwintering losses.) 

As I understand it, screened bottoms got started as a tool to control varroa. Experience and lots of studies show that screened bottoms, standing alone, will not protect a hive from varroa mites. If screened bottoms did have that effect, the varroa issues would have been licked a long time ago.

I have used both, and I don't see all that much difference.

Screens are good for mite counts and being able to close the hive and maintain air. In my experience, queens don't want to lay in the bottom box early in the year with an open screen, which I don't like.

Solids are cheaper, and you need to count mites with a sugar/alcohol wash, although that is a better way probably. You can also use a screen to close up a hive when needed.

I suspect all the "bees need ventilation" talk is off-base. Bees don't want ventilation in a natural hive cavity -- they propolize over the ventilation holes. What I really want to know is whether screened bottoms actually interfere with bees ability to cool the hive with water. Anybody who has ever used a swamp cooler to cool a house knows that it won't work if you keep your windows open. I don't know why it would be any different for bees. 

When I need a new bottom board, I've started getting solid ones at this point.


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## johno (Dec 4, 2011)

There are always pros and cons when you look at solid against SBB's. As I make my own I find it easier and cheaper to make SBB's. I will also close up the bottoms with coroplast during the winter months and even in the summer if new queens are to be mated in any hive, had too many queens return from mating flights and take up residence under the screen. But they have the advantage of being able to see the results of a mite treatment.
Johno


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## TylerStewart (Oct 15, 2014)

NeilV said:


> Anybody who has ever used a swamp cooler to cool a house knows that it won't work if you keep your windows open. I don't know why it would be any different for bees.


I'm not sure I totally agree with this.... Swamp coolers need a source of dry air coming in, and then the cooled air needs a place to escape. If you blow 'swamp cooled' air into a space, it will stop working if that air can't vent out a window or a door. We run one on our garage, blows air in from our sideyard, and we have to crack the garage door an inch or the cooling effect stops working.


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## Robbin (May 26, 2013)

I use both, I prefer SBB with the ability to add an oil tray (freeman beetle traps). It's the only thing I've found that really works against SHB. I leave them on year round, and have had 15 degree weather twice this year. Next few days we get 24, 25, 27 for lows, but are highs are usually in the 50s. Last week we had two 70+ high days. Bees take it all in stride.
I've stopped adding hives, now I will continue to add freeman beetle traps till I've got one under every hive.


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## Robbin (May 26, 2013)

MikeinCarolina said:


> I have used both the screened and solid bottom boards over the years - over the last few years I have been using the screened having read it helps with hive ventilation and mite reduction. I am wondering if there have been any studies done as to what works best or your own anecdotal evidence that one is superior to the other.


UF put out a study that SBB hives had 14% fewer mites sitting directly beside hives with solid bottom boards. 14% isn't enough to stop mites from killing your hive, but it helps...
No link, I was in a Bee seminary with a UF prof that was discussing raising bees in Florida.


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## Ross (Apr 30, 2003)

There hasn't been a concensus on any aspect of beekeeping in 150 years. I run screens.


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## ordy28 (Sep 10, 2013)

TylerStewart said:


> I'm not sure I totally agree with this.... Swamp coolers need a source of dry air coming in, and then the cooled air needs a place to escape. If you blow 'swamp cooled' air into a space, it will stop working if that air can't vent out a window or a door. We run one on our garage, blows air in from our sideyard, and we have to crack the garage door an inch or the cooling effect stops working.


What you are describing is positive pressure ventilation. Firefighters use it to vent a house. Blow a fan on an open front door with the air cone covering at least 90% of the door. Then open one window up stairs or at the other end of the house and within minutes the house will pressurize and you best not be standing in the path of that window. The amount of air moved is amazing and is quadruple the amount of venting using suction. So I imagine SBB would be similar. I would think the amount of air thru the SBB might be too much and hinder proper venting of the hive, in the proper proportion. Just surmising, I don't really know.....

I use both, but I wonder sometimes how much I really do to the mite count or if I am helping the SHB to enter and hide. Not to mention the SHB larvae allowed to exit through the bottom and mature under my hives where I can't get to them. Although my only two hives lost to SHB were in solid boards. But they were weakened by something else first, so I think the bottoms had little to do with it. I am moving back to solids as I build this year and time will tell.


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## AR Beekeeper (Sep 25, 2008)

How well the bees are able to ventilate a hive will show up in summer by how many bees you see clustering outside the hive. I think that if you have open mesh bottom boards you see less bearding in summer than with closed bottom boards. The bees will ventilate and maintain the humidity in the brood nest area by forming a shell of bees, and opening and closing the shell around that area, just as they form a cluster shell in winter.


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## Rader Sidetrack (Nov 30, 2011)

See this study reporting a 14% drop in varroa mites with a screened bottom:

http://www.ent.uga.edu/bees/publications/ABJ.pdf

Note also that they pointed out that the 14% drop was _not statistically significant_. They also said that there may be a trend in studies that suggest that screened bottoms reduce mite populations to some extent. If you want to incorporate a screened bottom, put it over an oil tray - to kill the mites - with a solid bottom beneath that to control airflow and allow evaporative cooling by the bees.


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## Cyan (Jan 27, 2015)

I had brought this topic up not too long ago in the equipment forum, concerning top entrance hives. From what I understand too much ventilation can be a real problem, and so is not enough ventilation. Both make perfect sense to me- all pest control aside. The bees however, seem to be best suited to regulating minor temperature fluctuations because they do this by nature. So I don't see the point in altering what happens naturally. 
However, what about the times when exterior hive temperatures reach extremes and causes stress? I'm probably speaking for the greater majority of small time beeks when I say that we can't possibly babysit our hives 24/7. 

Now here is where I go a little crazy on the subject: It seems to me that such a solution could be devised to provide additional ventilation or reduced ventilation as needed, through technology. A smart hive if you will. The simplest method could utilize a bi-metal coil that would open a vent- similar to the old style furnace thermostats. The most complex could range from internal sensors, electronics, and small- low voltage motors to open vents or even something like the heat pipes used to cool CPU's. Want to add heat? Solar and battery combo with a small heating element. Surely no one wants to pay more or do more maintenance that what's necessary, but the technology is there to provide solutions to heating/cooling. The only question is whether it's worth it and I'm sure that this would be climate based.


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## Cyan (Jan 27, 2015)

14% less of anything is significant in my book. Plus, I'm a firm believer that any study older than 10 years old isn't all that valuable- to me anyway. Seems that there should be new studies. Does anyone here keep personal journals that could add to the mix?

Another thought I just had was as to when most of our 'modern' beekeeping knowledge was added. We are talking about knowledge that is well over 100 years old. Think about that for a minute- how many people actually forget that the older hives were made of thicker wood, thus altering a hives insulating capabilities? It could just be that the little bits and pieces that we are overlooking from over many years of history, is causing us issues that don't have to be.


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## Rader Sidetrack (Nov 30, 2011)

If you flip a coin 10 times, and 6 of those flips come up 'heads', then there are 20% less 'tails'. But 10 flips are not enough flips to make that 20% difference _statistically significant_. Even if the 'study' _was _run more than 10 years ago.


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## mc1960 (Jul 28, 2014)

If the bees thought that they had too much ventilation, would they not just seal it up?


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## Matt F (Oct 7, 2014)

ordy28 said:


> What you are describing is positive pressure ventilation. Firefighters use it to vent a house. Blow a fan on an open front door with the air cone covering at least 90% of the door. Then open one window up stairs or at the other end of the house and within minutes the house will pressurize and you best not be standing in the path of that window. The amount of air moved is amazing and is quadruple the amount of venting using suction. So I imagine SBB would be similar. I would think the amount of air thru the SBB might be too much and hinder proper venting of the hive, in the proper proportion. Just surmising, I don't really know.....
> 
> I use both, but I wonder sometimes how much I really do to the mite count or if I am helping the SHB to enter and hide. Not to mention the SHB larvae allowed to exit through the bottom and mature under my hives where I can't get to them. Although my only two hives lost to SHB were in solid boards. But they were weakened by something else first, so I think the bottoms had little to do with it. I am moving back to solids as I build this year and time will tell.


Guys you are making too many assumptions on the evaporative cooling. It can work both ways. If you're trying to cool to below ambient temperature and the ambient air is very dry, say 20% humidity, then too much air will keep the temperature elevated, at least close to ambient temp. But it's also true that no air flow is far worse. If the ambient air is very humid, above 70% and/or ambient is cool enough for the hive, i.e. you just need to cool off the solar radiation heat, then more air flow is better and evaporative cooling is minimal without substantial air flow.

If I lived in the high desert of California a solid bottom would probably be better, with vent holes on two sides top and bottom, but here in Maryland where summers are very humid but temps don't get much above 100 deg F, the ventilation of a SBB is beneficial.


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## Cyan (Jan 27, 2015)

http://www.extension.org/pages/65450/varroa-mite-reproductive-biology#.VNovZ-ktG00

My thoughts on this were based on knowledge I picked up on stink bugs. That may seem irrelevant, but the situation is somewhat similar. 

If one removes 14% of the mite population it's not that bad as far as a form of control is concerned and here's why. According to the link I provided, a mite can lay 5-6 eggs per cell. So for every mite that is not removed multiply x5 or x6. Only so many of those will be female, but even if 3 females emerge you are now adding an additional 15-18 and so on. Varroa are also similar to bees, in that a female doesn't need inseminated to produce male offspring. I'm not knowledgeable enough to guess how many mites are in an average colony of bees, but I think if you do the math, 14% can make the difference (over time) between having the mites in check or having them quickly infesting a hive. Idk, maybe I'm wrong but I think the evidence that I see tells me that every little bit helps.

p.s. apologies if the link doesn't post right


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## Matt F (Oct 7, 2014)

Cyan your logic holds true if there's a 14% greater mortality rate in any given life cycle of a mite (before reproduction) but that's not what it says. An overall mite reduction of 14% across the year has already accounted for the multiplication of many life cycles through the year. For example if you kill 3% of the mites and there are 4 life cycles, the net decrease at the end will be 1 - 0.97^4. which is 11.5% reduction in total mite population. So if there are 4 life cycles (which is a COMPLETE guess) and you only reduce mites by 3% per cycle, the net decrease is 11.5% by the end of the season. Small changes create big changes by the end of the year.

Still, if we can get 14% with little to no down side, it's definitely worth it.


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## JWChesnut (Jul 31, 2013)

I run screen bottoms on approximately 1/4 of my colonies. All my SBB have a solid drawer insert installed all the time. I have no SHB, so this is not a concern. Hive trash and mites fall through to the solid sheet. They are useful for inspecting the condition of the hive without opening it up --- so I run them on singles that I am watching establish.
You can see mites, cappings, pollen, antenna casts from hatching brood, eggs that are dropped. From the trash you know where the queen is located, and how many frames are in brood. I always look at the debris before opening the hive.

Downside -- small Argentine ants can enter hives with SBB more easily. If you don't clean the boards every 3 weeks (or so) Wax moth will begin to hatch in the debris.

I don't see any significant effect on mites in the SBB per se, and the mite fall doesn't begin to characterize the loading in the hive. A sugar dust on the frame slots will carry a lot of mites down onto the board, and this does inform the actual loading in the hive. The sugar dust draws ants. I've never found the sugar dust sufficient to prevent PMS in the fall.

My SBB are my own design using scrap sheet good pallet binding boards (already dado cut). The 2x3 side rails give the BB a lot of strength compared to the 1x3 commericial designs. 








A more complete photo-essay on this construction : http://www.beesource.com/forums/showthread.php?306812-SBB-from-Pallet-Scrap


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## Nabber86 (Apr 15, 2009)

I do not see how a SBB provides extra ventilation if you don't have a top entrance.


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## D Coates (Jan 6, 2006)

I've got 25 hives. Up to the first 15 I was running all SBB. I tried a few solid bottoms to see if there's a difference. I noticed none of any form in the past 3 years so I've now got 10 solid bottoms. I do have a 2 inch shim above inner covers with a 1 1/4" hole in it, below the outer cover on all of my hives at all times. All of my hives are in full sun. I've noticed no bearding differences in the dead of summer. As winter comes in I cork the entrances and bottoms to help keep winter out. It's a bit of a pain with the SBB's and hauling their covers. As they age I'll replace them with solid bottoms unless I notice something new.


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## green2btree (Sep 9, 2010)

Concensus? :lpf::lpf::lpf:

JC


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## Vance G (Jan 6, 2011)

Lets see. We are housing insects of tropical origin who need to maintain 93 F in their brood nest to raise brood and can only raise an amount of brood that they can keep at that temperature. Putting a gaping hole in the bottom of their domicile helps accomplish this how? These insects if given a choice, almost always choose a cavity with one entrance and for million years have masterfully ventilated that kind of cavity.

I think the fact bees manage to survive when such faddish things are inflicted on them shows how tough the species is!


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## rweaver7777 (Oct 17, 2012)

My SBB have oil traps underneath so while screened to capture beetles and mites, are closed to the outside air.


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## green2btree (Sep 9, 2010)

Hey JW, who uses that kind of pallet? The ones I have always seen just nail boards on top of a shallow box or three runners.

JC


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## JWChesnut (Jul 31, 2013)

green2btree said:


> Hey JW, who uses that kind of pallet? The ones I have always seen just nail boards on top of a shallow box or three runners.


The dado'd 2x3 are the spreader boards use to bind pallets of sheet goods (panel, hardie, ply) as sold at the big-box Home Improvement retailer. All the locations I know load these boards into shopping carts as trash (with the strapping, stickers, etc). They are glad to see them gone. The spreaders are 45-46" long, and when cut in half can be bookmatched to make the SBB side rails. The "stile" pieces are connected with cabinet biscuits, and a single screw in lieu of a clamp.

A more complete photo-essay on this construction : http://www.beesource.com/forums/showthread.php?306812-SBB-from-Pallet-Scrap


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## TalonRedding (Jul 19, 2013)

JWChesnut said:


> I run screen bottoms on approximately 1/4 of my colonies. All my SBB have a solid drawer insert installed all the time. I have no SHB, so this is not a concern. Hive trash and mites fall through to the solid sheet. They are useful for inspecting the condition of the hive without opening it up --- so I run them on singles that I am watching establish.
> You can see mites, cappings, pollen, antenna casts from hatching brood, eggs that are dropped. From the trash you know where the queen is located, and how many frames are in brood. I always look at the debris before opening the hive.
> 
> Downside -- small Argentine ants can enter hives with SBB more easily. If you don't clean the boards every 3 weeks (or so) Wax moth will begin to hatch in the debris.
> ...


Well put....especially on being able to see what's going on in a hive without opening it up. They've been extremely helpful for me during dearths when robbing is almost guaranteed if colonies are opened. I think a lot of folks attempt to use them to control varroa, which does not work by the way, but they can be used to MEASURE varroa. Mine are closed up all year.


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## Rob Hughes (Apr 23, 2012)

A lot of people seem to assume using a sbb means air whistling up from below, but if you use a design with a drawer slide below, this is not the case, as some have noted. I make my own sbb and they are almost exactly like the one JWChestnut showed. I make the drawers from sheets of pre-painted white aluminum flashing which is available in nice wide sizes, scribe on a grid, and you have a permanent mite-drop and general hive state assessment system....I coat them with a thin layer of vaseline. You can often identify which pollen sources are being worked, as well as all the other factors noted by JWC. I think the jury suggest that the sbb will not effectively control mites, but may be the most useful mite load monitoring method as it always reflect the total colony load as opposed to the infestation rate, which is what you get from the alcohol wash method. In winter I stick a slab of rigid insulation under the drawer slide. There is very little air leakage.

Another thing -all the frass and stuff that drops through does not have to get packed out by house bees, freeing them up for other duties.

Rob


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## mac (May 1, 2005)

switching back to all solid bb. seems harder to control robbing with all the extra ventilation bringing out the smell of honey


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## Acebird (Mar 17, 2011)

mac said:


> seems harder to control robbing with all the extra ventilation bringing out the smell of honey


Then how does a robbing screen work?


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## Acebird (Mar 17, 2011)

NeilV said:


> Anybody who has ever used a swamp cooler to cool a house knows that it won't work if you keep your windows open.


And it won't work in a closed room with high humidity. The moisture gain has to be vented some how. If your attic is closed and not ventilated you can't let the heat out by opening the attic stairwell door. A SBB will allow moisture to pass out the bottom of the hive and aid the bees using evaporation cooling. If the screen was at the top of the hive you would have serious air flow which would be detrimental to the bees.


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## Nabber86 (Apr 15, 2009)

Rob Hughes said:


> I make my own sbb and they are almost exactly like the one JWChestnut showed. I make the drawers from sheets of pre-painted white aluminum flashing which is available in nice wide sizes, scribe on a grid, and you have a permanent mite-drop and general hive state assessment system....I coat them with a thin layer of vaseline.
> 
> Rob


Do you have any pics that you can post?


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## NeilV (Nov 18, 2006)

Ace, you're assuming that the choices are a screened bottom or a no airflow at all. However, on all my hives (both with and without screens), there is some ventilation always, in the form of bottom entrances, top entrances, cracking open the tops and/or old ratty boxes with holes in the corners. I've noticed the bees will propolize the holes and cracks in hive boxes in winter but will open them up in summer to use as entrances and maybe for more ventilation. They do that whether or not there is a SBB, so I don't know that ventilation is the key. 

Cyan, I think your understanding of varroa mite reproduction is a bit off. The foundress mite lays in a cell, and the first egg is unfertilized (male), the rest are fertilized (female). The siblings then mate in the cell. Only the mated female offspring are able to reproduce, and they are the ones to worry about. Although the mother mite may lay 5-6 eggs, in a drone cell only 2 or 3 viable female offspring result. In a worker cell, roughly 1 viable female mite gets added. 

On the mite drops, here is another consideration: what if the mites that are dropping are, on average, just old mites? I don't know how long Varroa mites live, but they don't live forever. I don't claim to know the answer to this question, but it would affect the math.

In the SBB vs. varroa department, another issue/question is the effect of temperature on mite reproduction and how SBBs relate to that factor. As I understand it, Varroa mites are supposed to be in Apis cerana hives, and they are supposed to reproduce in drone cells that are built outside of the brood area and are a little cooler. It is also my understanding that, apparently for this reason, Varroa reproduce a little better in cells that are a little bit cooler than normal brood nest worker cells, although I cannot remember the temperatures. One possibility is that the screened bottoms, under certain conditions, may actually cool the hive and make it more comfortable for the mites. In other situations, the SBBs mite make the hive hotter and make conditions worse for the mites. If that is the case, then the effectiveness of SBBs in mite control would be more complicated than just how many mites fall, since the SBBs would also affect the mite reproduction, due to affecting temperatures. 

As I said above, just looking at my hives with and without SBBs, I cannot tell any difference. Maybe the SBBs help in some ways and hurt in others???


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## Rader Sidetrack (Nov 30, 2011)

Here's a page that supplements Neil's summary of varroa biology/reproduction ....

http://www.ars.usda.gov/Research/docs.htm?docid=2744&page=14


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## philip.devos (Aug 10, 2013)

GaSteve said:


> I read the thread title and had to chuckle "Is there a consensus...". I think the consensus is there is never a consensus on anything in beekeeping.


I consent with your consensus regarding consensi (sp?). :lookout:


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## NeilV (Nov 18, 2006)

philip.devos said:


> I consent with your consensus regarding consensi (sp?). :lookout:


I think that's ridiculous.


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## D Coates (Jan 6, 2006)

Rader Sidetrack said:


> Here's a page that supplements Neil's summary of varroa biology/reproduction ....
> 
> http://www.ars.usda.gov/Research/docs.htm?docid=2744&page=14


Very cool. I'd not seen it laid out that well before.


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## NeilV (Nov 18, 2006)

Here's what I want I'm not clear on: what happens to the unmated female mites that are in the cell when the bee emerges? Do they emerge at all, and, if so, what happens to them?


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## Sticky Bear (Mar 15, 2012)

D Coates said:


> Very cool. I'd not seen it laid out that well before.


 Excellent read, thanks Coates.


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## Rader Sidetrack (Nov 30, 2011)

>> what happens to the unmated female mites that are in the cell when the bee emerges? 

The implication (but not stated explicitly) is that the non-mature/non-mated female mites do not leave the brood cell alive, and the bees dispose of them along with the male mite.

From 'Step 20' of that same ARS page:



> In most cases, the mother mite and only 1-2 mature daughters will leave the brood cell. An average of 1.4 - 1.5 daughters per mother mites is typical for a population of mites.
> 
> The male mite usually remains in the brood cell. He will be killed and removed by nest cleaning bees that prepare newly vacated brood cells to receive another egg from the queen bee.
> 
> http://www.ars.usda.gov/Research/docs.htm?docid=2744&page=14


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## Cyan (Jan 27, 2015)

D Coates: thanks for the link. That was a bit more explanatory to me.


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## scorpionmain (Apr 17, 2012)

NeilV said:


> Here's what I want I'm not clear on: what happens to the unmated female mites that are in the cell when the bee emerges? Do they emerge at all, and, if so, what happens to them?


From my limited understanding, they mate with their brothers that are in cell with them before emerging.


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## NeilV (Nov 18, 2006)

Not all the females mature enough to mate before the bee emerges. We are talking about what happens to those mites.


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## scorpionmain (Apr 17, 2012)

NeilV said:


> Not all the females mature enough to mate before the bee emerges. We are talking about what happens to those mites.


Ah, I always took for granted they were.


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## WD9N (Dec 28, 2014)

GaSteve said:


> I read the thread title and had to chuckle "Is there a consensus...". I think the consensus is there is never a consensus on anything in beekeeping.


That is exactly what I was thinking when I read it! 

I have been studying for a few years on bees and am just getting started, but the one thing I have found is there is NO consensus. There are so many ways that work for any given situation for any given colony in any given. It just seems like you find what works for you and your bees and go with it.


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## Michael Bush (Aug 2, 2002)

I think beekeepers did have a consensus once. It was a consensus that there was nothing in beekeeping on which beekeepers ever had a consensus... then recursion set in...


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## johno (Dec 4, 2011)

Lets get a little political here, I was for consensus before I was against consensus


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## Acebird (Mar 17, 2011)

NeilV said:


> Ace, you're assuming that the choices are a screened bottom or a no airflow at all.


Not really. My comment is in reference to a swamp cooler which doesn't work well in a high moisture environment which a bee hive is. Adding ventilation will help the swamp cooler not hinder it. It is not a freak of nature that the bees get out of the hive when it is too hot.


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## Acebird (Mar 17, 2011)

NeilV said:


> We are talking about what happens to those mites.


They die Neil.


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## Rader Sidetrack (Nov 30, 2011)

Acebird said:


> My comment is in reference to a swamp cooler which doesn't work well in a high moisture environment which a bee hive is.


Evaporative cooling doesn't work well in a "high moisture environment"? You mean like the southern USA states with high humidity ?? :scratch:

Ace, there are chicken farms (broiler production) all over the humid South that cool their broiler houses with *evaporative cooling*, i.e. swamp coolers. I've seen them myself. There are plenty of articles about these systems. Here's one from Auburn University - in {humid} Alabama: 

http://www.aces.edu/poultryventilation/documents/GetMostEC.PDF

In term of beehives, when the ambient temperature exceeds 94 degrees F, which occurs with some regularity in the {humid} southern USA how do you explain bees being able to maintain their brood nests at 94 degrees if evaporative cooling doesn't work? :s Obviously, it works _well enough_ for the bees to thrive.


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## Acebird (Mar 17, 2011)

If you read the PDF they state that air flow is key to making it work. The bees do exactly the same thing they remove all non essential personnel from the hive and then the remainders beat hell out of their wings to move air.

You can feel this effect if you sit in the shade with a fan on you. Then go sit in the house with a fan on you and you will be able to tell the difference. The house will trap moisture and heat from your body and the result is the cooling decreases.


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## Rader Sidetrack (Nov 30, 2011)

Acebird said:


> You can feel this effect if you sit in the shade with a fan on you.


Ace, humans _SWEAT_! (OK, well reportedly, _ladies _merely _glow_.).
And sweat is part of the human _evaporative cooling_ process! 


No matter how much 100 degree air you move with a fan (or thousands of bees' wings), without evaporative cooling, that air is *still *100 degrees. I ask again, *how do the bees get the brood nest to 94 degrees when the ambient temperature is 100 degrees?*:scratch: They certainly can't do it just by airflow alone, the incoming air is also 100 degrees!

:ws:


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## doug reed (Feb 1, 2014)

JWChesnut said:


> I run screen bottoms on approximately 1/4 of my colonies. All my SBB have a solid drawer insert installed all the time. I have no SHB, so this is not a concern. Hive trash and mites fall through to the solid sheet. They are useful for inspecting the condition of the hive without opening it up --- so I run them on singles that I am watching establish.
> You can see mites, cappings, pollen, antenna casts from hatching brood, eggs that are dropped. From the trash you know where the queen is located, and how many frames are in brood. I always look at the debris before opening the hive.
> 
> Downside -- small Argentine ants can enter hives with SBB more easily. If you don't clean the boards every 3 weeks (or so) Wax moth will begin to hatch in the debris.
> ...


What have you come up with for the slide in tray? Love the 2x3 adaptation. I often looked at those wondering how I could use them for something other that firewood.


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## Lauri (Feb 1, 2012)

Why not have both?
Summertime ventilation without being drafty, good wintertime drainage & circulation. Durability of a mostly solid bottom


http://i425.photobucket.com/albums/...926001/2014 bee pics/P1010041_zps5b7960a4.jpg


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## mac (May 1, 2005)

Acebird said:


> Then how does a robbing screen work?


 Come on man you KNOW how it works


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## yem (Jan 19, 2010)

I use both and am still torn......I live in a holler on a riverside so humidity is a huge issue. Last summer it seemed that the solid bottoms cured the honey a wee bit faster.....but that's not to say there may have been more workers fanning it cause maybe it was warmer in the hive.


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## barberberryfarm (Feb 16, 2013)

I switched to SBBs because I got tired of cleaning the solid boards which for me was no easy task to even inspect when you have 3-4 boxes on top of it. However, I also have a sealed compartment under each of my SBBs to house a catch tray of diatomaceous earth. This way excess ventilation is not an issue while the hive debree and unwanted critters (larva, SHBs, mites, etc.) fall through to the DE covered trays which I periodically clean with relative ease.


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## laketrout (Mar 5, 2013)

Does diatomaceous earth stop mites from going back into the hive or just the beetles .


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## NeilV (Nov 18, 2006)

I don't think mites are going to make it back into a hive if they fall through a SBB. The problems appears to be that, for whatever reason, the decrease in mite population from SBBs, standing alone, does not seem to be sufficient.

I would be very careful with diatomaceous earth used for any purpose around a hive. It cuts up insect bodies and kills insects and larvae. It would be bad for bees too. It is windy enough in Oklahoma that I would be worried it would get blown where I do not want it to be (inside the hive or where bees could get on it. I do use it in my chicken coop for lice.


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## odfrank (May 13, 2002)

>I switched to SBBs because I got tired of cleaning the solid boards which for me was no easy task to even inspect when you have 3-4 boxes on top of it.

I switched AWAY from SBB for the same reason. Bees do a pretty good job of keeping solid bottom boards clean and many don't even need cleaning annually. But they can't get to the trays of SBB, the trays become a breeding ground for wax moth and SHB larvae and REQUIRE cleaning at least twice a year. So that makes for MORE work than a solid bottom board unless you go to a bottomless hive. And that makes a mess if the debris can't fall straight to the ground, as when the hive sits on a stand with a plywood top.


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## barberberryfarm (Feb 16, 2013)

NeilV said:


> I would be very careful with diatomaceous earth used for any purpose around a hive. It cuts up insect bodies and kills insects and larvae. It would be bad for bees too. It is windy enough in Oklahoma that I would be worried it would get blown where I do not want it to be (inside the hive or where bees could get on it. I do use it in my chicken coop for lice.


That's why I sealed the compartment so the wind, rain and bees couldn't get in there and the DE so far has worked great at killing the wax moth/SHB larva as well as the mature SHBs that fall through the screen.


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## barberberryfarm (Feb 16, 2013)

odfrank said:


> >I switched AWAY from SBB for the same reason. Bees do a pretty good job of keeping solid bottom boards clean and many don't even need cleaning annually. But they can't get to the trays of SBB, the trays become a breeding ground for wax moth and SHB larvae and REQUIRE cleaning at least twice a year. So that makes for MORE work than a solid bottom board unless you go to a bottomless hive. And that makes a mess if the debris can't fall straight to the ground, as when the hive sits on a stand with a plywood top.


The bees in my hives took care of cleaning their bottom boards about 50% of the time. However, I never knew which hives were good housekeepers and which weren't without tilting the hives (which was no easy task). The ones that weren't very hygenic sometimes had deep piles of debree which the wax moth/SHB larva had boroughed into and I had to swap out bottom boards as cleaning them in place was not an option. However, now with the SBB the larva (as well as adult SHBs) fall through the screen and are cut to shreads on the DE instead of wiggling their way outside, burroughing into the soil until they emerge as adults to once again raise havvock in my hives. As far as work goes cleaning the trays, it takes about 2-3 minutes and I can easliy check on their status every month or so during the spring and summer just for my piece of mind. 

So *FOR ME* the SBB combination that I use in conjuction with the OJ Blount custom hive setup that I use works best. Now maybe down the road I may change my mind, but that's one of the fun things fun about beekeeping, there are 1000's of different combinations to try in search of that perfect bee hive. Speaking of the OJ Blount hive, which has worked extremely well for me so far, here are a couple of pictures to go along with the SBB picture I posted earlier.


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## snl (Nov 20, 2009)

IMO.....go with a Solid BB. Look at the brood in a Sc BB ......it's above the screen considerably. So that tells me the bees don't like the draft. Also a SoBB is easier to build.... and it's easier to vaporize (OAV) with a SoBB, no screen to close up.......


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## NeilV (Nov 18, 2006)

Barberryfarm, 

Could you start a thread showing your set up with photos? Sounds interesting, but I don't have enough pictures or information to understand what you're doing exactly. Probably deserves a separate thread too.

Neil


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## barberberryfarm (Feb 16, 2013)

NeilV said:


> Barberryfarm,
> 
> Could you start a thread showing your set up with photos? Sounds interesting, but I don't have enough pictures or information to understand what you're doing exactly. Probably deserves a separate thread too.
> 
> Neil


Niel, I posted this thread on the custom OJ Blount hive setup I'm using awhile back. Hope it helps.

http://www.beesource.com/forums/sho...-Boards-an-impressive-design&highlight=blount

Ken


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