# double layer or single?



## davemal

For a science center which wishes to have a long-lived OB hive, should they go with a double layer or single layer OB hive? Single layer allows queen to be seen, but does it provide the resources to support a sufficient number of bees?


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## ruthiesbees

How many total frames is the observation hive? Or will it be custom built to the specs you decide? My display hive is a single layer because I only take it to weekend shows, and everyone wants to see the queen. But if I was to have a colony actually live in an observation hive, I'd have to go with a double layer, unless the beekeeper is wanting to constantly be adding/subtracting frames of whatever the colony needs.


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## davemal

Ruth, looking at a double wide with a total of either 6 or 8 deep frames. Probably will go with 6. Bonterra sells double wides. Draper can custom make a double wide. Having a single layer hive makes sense for shows. Also for an experienced beekeeper with lots of resources and management ability. Draper has had his single layer OB hive alive for 26 years! But he knows how to manage and has the resources at hand such as needed to add an extra frame of honey now that the warm weather has his bees eating their stores. But the educational center will not have that luxury to go in often. We local beekeepers will help, but maybe having more resources in a double layer hive would offset the downside of not being able to see the queen very often.


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## D Coates

A single layer works fine. I've got a single 5 frame deep. It's been running for 4-5 years continuously. I won't say I've not had to work it now and again but I have to do that with all my hives. Queens last 1-2 years. Doubles won't let you really see what going on in there, especially if they're working up swarm cells or the queen is failing. People who see the hive ALWAYS want to see the queen. She'll hide in between the frames if she can if it's a double. Not seeing eggs if/when there's a queen issue will be a whole lot tougher and you'll end up getting into the double layer more often or not realizing you're hopelessly queenless until it's too late.


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## davemal

D Coates, your single wide has 5 deep frames? We are looking at a 3 or 4 deep frame single-wide OB hive. Does the fact that you have so many frames (5) make it easier for the hive to survive - as opposed to a single wide hive that is only 3 or 4 deep frames high?


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## rookie2531

I think smaller amount of frames just makes it harder to stop the swarm. Don't the ob hives your looking at come with a jar type feeder hole? You can mix sub with syrup if they get low on stores.


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## D Coates

davemal said:


> D Coates, your single wide has 5 deep frames? We are looking at a 3 or 4 deep frame single-wide OB hive. Does the fact that you have so many frames (5) make it easier for the hive to survive - as opposed to a single wide hive that is only 3 or 4 deep frames high?


Sorry for the delay. I didn't see this question. Yep, single wide 5 deep frames. Personally I think so, that's why I had it made that way.


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## D Coates

rookie2531 said:


> Don't the ob hives your looking at come with a jar type feeder hole? You can mix sub with syrup if they get low on stores.


I've done this with mixed results. The sub has to be VERY weak and even then it settles out. In the big picture very little substitute seems to get consumed. The syrup feeding works just fine though.


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## texanbelchers

I missed the entire thread. We have an OB hive in our butterfly center. It was originally single layer with 3 deep and a shallow. When I got involved they informed me it was constantly (2-3 times per year) absconding or swarming. It may have been worse in our climate or poor ventilation in the hive. Last year it was rebuilt into a double layer for 6 deep and 2 shallow. The spacing was planned for 1 3/8 frames, but the bees I installed were on 1 1/4 frames. It was off enough that they built a 3rd layer in a one sided big sheet. It looks really cool, but it covers nearly an entire side of the hive and you can't see any activity under it. They were still drawing comb into November, but have slowed way down. They haven't had a year in the hive yet, but they have much more space to work with. Some bees hang out on the shallow foundation, but they haven't drawn it out at all.

I couldn't do it due to the building design, but I would suggest providing some way to work it from outside. It is a real pain to close it up and move it outside which discourages regular maintenance. Also, make sure all tubes, slides, doors and feeders are screwed securely. Bees loose in public space is frowned upon.


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## davemal

D Coates, I work with a different Nature Center that has a nice homemade OB hive with 9 frames (three layers of three deeps in each layer). The first layer is all drawn comb on all three frames. Last summer when we set it up, we put starter strips in the remaining 6 frames and had a great time watching the bees draw out the middle two frames. Not so much drawing out on the other starter strips, though. We have a syrup feeding port at the top center. But the #8 hardware cloth that the feed jar sits on top of gets propolized often! We added a pollen sub feeding port at the top off to one side. It has a couple levels of hardware cloth. The bottom is 1/2" hardware cloth that the bees crawl through to get the sub. Then a space we fill with pieces of pollen sub. Then on top of that there is a removable small wooden frame with #8 hardware cloth so bees cannot get out. We quickly remove it in order to add more sub. The pollen sub feeding port is covered with a piece of Plexiglass so we can see what is going on with the pollen sub.


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## D Coates

davemal, Interesting. I've not considered a separate feeding port for substitute. By the time they need sub the OB hive is at it's weakest in early Spring. I've had SHB larva start up a few times and didn't really consider it as my feeder is at the bottom of the hive and it could easily exacerbate the issue. Watching SHB larva squirm about while waiting for a warm day to deal with them isn't fun.

I put added effort this year to encourage population growth in early Fall with my OB hive. With higher population they'll better dispose of the dead all the way to spring. It's in this dead build up at the bottom of the hive that the SHB eggs get laid and hatch unmolested. So far the hive has done well and there are absolutely no dead in the hive.


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## Michael Bush

Everyone wants to see the queen. I would only do single layer. If I can't see everything that goes on, what is the point of an observation hive?


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## texanbelchers

I think a lot has to do with the purpose and location of the hive. Our visitors are there to see the butterflies and the bees are a nice thing to have. They stay there for no more than a couple minutes; normally less than one. Most get easily distracted by a Blue Morpho going by. Those that want to see the bees enjoy watching whatever they can see. We get a lot of comments when the hive is empty; not too many when they can't see the queen.


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## brushwoodnursery

I work 2 OHs and have just built a third.
One is a weird mix of 3 deeps up the front with 2 more deeps inside along the bottom. We never see the queen on the front face. It's also brutal to work; dozens of screws to get in and heavy as a pile of bricks.
The other is 2x4 deeps. I think it's a bonterra. Back in the fall, I started managing it for a local school. Put an underperforming colony into it that seems just the right pace. The other days I walked up to it and immediately spotted the queen. Plenty of brood was visible at different stages to show the kids, too. 
So, based on that, I decided at the last minute to switch over from my planned single to a double. I'm also going to try 1/4 plexi instead of glass. If i get the beespace right, I'm hoping they won't burr it up too much. I have them at 3 1/4". Does that sound OK? I'll try posting pictures. maybe start a new thread.


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## IAmTheWaterbug

D Coates said:


> Watching SHB larva squirm about while waiting for a warm day to deal with them isn't fun.


I'd love to have a laser of the appropriate wavelength handy so I could zap 'em through the glass.


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