Comb

Small cell bees were transferred into my first top bar hive.
Small Cell Bees In A Top Bar Hive
A top bar hive is essentially an empty box with bars, or top bars, where the bees hang their comb. In a top bar hive, the bees build comb their way. It's a great tool for natural comb observations. Here's what I saw.

Measurements indicate cell size decreases down the comb's length.
Speed
Natural comb is drawn fast and effortlessly. My top bar hive more than kept pace with my standard hives and their drawn comb frames. Comb building was so effortless that neither brood nor honey production lagged behind my standard hives. Producing sufficient comb is no problem when bees do it their way.
A top bar comb failed. Three days later I returned to document the failure. I couldn't determine which comb had failed. The bees built it back that fast.
There's something about foundation that slows the bees down. My standard hives drew only 2 frames of foundation while the top bar hive built 20 frames worth.
Beauty
Natural comb is beautiful. It has a complexity and visual texture that foundation based comb lacks. Colony development follows the comb's advancing shape. So brood and pollen appear oriented toward the comb's bottom, rather than the top. That's an unusual sight for anyone who has worked with standard equipment. Natural comb is very fascinating.
Priorities
Comb building seems rather haphazard. But the bees collectively sense what broodnest structure is needed. Then they match colony strength and environmental conditions with colony needs. Sometimes they need more storage. So, they shift their focus and build storage comb toward the hive's far end. At other times, more brood comb is needed. So, they return to the broodnest core and work there. When they are done, they've constructed a broodnest with the right comb, in the right place.

Horizontal queen cup.
Worker comb gradually transitioned from larger worker cell size toward the top of a comb to smaller worker size at the bottom. It was unlike the more drastic transitions in cell size I'd seen before when bees rework foundation.
Parallel versus Straight Comb
Bees build parallel comb, but not necessarily straight comb. Bees curve the comb ends toward the hive's front. The curvature increases in combs toward the hive's far end. Curved comb is much stronger than straight comb. It may also provide some advantage with hive ventilation.
Comb Measurements
I photographed the comb with a scale and used methods to minimize optical distortion. These photos were used to measure cell size. Cells were measured perpendicular to the cell walls. Areas of different cell size were delimited and contoured.
After contouring, a square grid was scaled and drafted for each photo. Squares were counted and totaled for each delimited area. And totaled for the entire hive.
Here are the percentages for each top bar. The hive entrance is near top bar 2. The composite results for the entire hive are in the total column.

Here's the same data graphed.

It's a good two dimensional representation of the hive structure. Colors toward the red end of the spectrum are drone and storage size cells. Colors toward the blue end of the spectrum represent worker size cells.
Drone sized cells occupy 18 percent of the broodnest. Large cell size made up about 60 percent. And small cell size about 22 percent.
There's more small cell comb toward the hive's entrance and none toward at the hive's rear. Drone comb was mostly drawn on the hive's right side, away from the entrance. Worker brood was generally drawn on the left side, nearest the entrance. Vertically, the larger cells were closest to the top bar. Cell size decreased toward the comb's bottom.
These small cell bees raised worker bees in cell sizes that ranged from less than 4.6mm to 5.59mm. And drones were raised in cells from 5.25mm to 7.29mm

David's Top Bar Hive.
Large Cell Bees In A Top Bar Hive
David, a beekeeper in Ohio, sent me comb photographs from his top bar hive. David started this hive, in March, from package bees. They completed 26 combs by the first part of August. And they were working on a couple more toward the hive's front. This comb was very straight. Most frames had capped honey stored above the brood. Two combs were harvested, leaving 24 full sized combs for analysis.
I asked David how he managed his top bar hive. He wrote:
"Yes this hive for some reason got a lot more attention than my other two. All of the Top Bars that were "thicker" were added. I also moved combs around. So if there was crooked comb, (defined as comb that interfered with my ability to remove the top bar cleanly) I would cut the comb, and in several instances, I replaced entire top bars. Then I would move completed bars and sandwich the new bars between the established comb in the hopes that it is straight. These new bars were of the triangle variety."
Most top bar hives are managed this way. So, I repeated the same measurement process.
Top bar 1, in David's hive, is located at the hive's rear, farthest from the entrance. Here are the results from David's hive.

Here's the same data graphed.

Top bar 28 is near the hive entrance. Top bar 0 is the total or composite for the entire hive.
The cell sizes and comb construction seen in David's hive are very similiar to those seen in my top bar hive.

Barry's top bar hive.
Lusbees In A Top Bar Hive
Barry, a Illinois beekeeper, also sent me comb photos. He built an interesting top bar hive. Its shape approximates a catenary curve. It's wide, deep and has a large volume. The top bars are reinforced with a slat and wire.
He stocked his top bar hive with a split from one of his small cell colonies. These bees, called lusbees, were originally obtained from Ed and Dee Lusby in Arizona. They have since cross bred with his local stock.
Several deep, small cell brood frames were screwed to top bars and put in his hive. These frames were removed once the bees had drawn enough natural comb to sustain themselves.
His management style was completely laissez faire. Once the bees were established, he left them alone to build a natural broodnest. The hive was opened a few times and preliminary comb photos were taken.
So, I did it again. Measured the comb like before.
Here are the results, in percent, from Barry's hive:

And the graph.

The hive entrance is near top bar 6. Top bar 13 consisted of two small pieces of comb intertwined with top bar 14. That comb is included with top bar 14 measurements.

Joe Waggles feral hive.
No surprises here. The cell size distribution mirrors that found in the other top bar hives.
Joe Waggles Feral Hive
Joe Waggle sent me a photo of a feral hive. This hive was inside a wall. This tall, narrow cavity had a very different shape compare to the top bar hives.
Unfortunately, this photo wasn't composed for comb measuring. It wasn't scaled. And, all comb wasn't visible. But the cavity was narrow, about two combs wide. So, I had a view of half of the comb. This feral hive had enough representative comb, with enough resolution to measure.
Joe had measured the smaller cells at the bottom of the comb. They consistently measured about 4.9mm per 10 cells. So, I located the smallest cells at the bottom. Using these cells, a ruler was scaled and pasted into the photo.
Because this shot wasn't composed for comb analysis, there are additional considerations. First, this is more camera distortion. Second, This taller comb had more irregular curvature. Some curved comb was harder to measure.
So, I did it again. For the last time, I hope. :>) I measured Joe's comb. Additional comb extends below that show in the photo, so I've rounded the actual figures :

These figures approximate those found in the top bar hives.
Measurement Comparison
It's interesting to compare the composite measurements side by side.

Discussion
These measurements are in the same range except for the smaller cell comb in David's hive. It's easy to conclude that David's large cell bees didn't build much small cell comb. But, I saw the same gradual decrease in cell sizes that I saw in the other top bar hives. There was one big difference. David's comb was much shorter because his hive was shallower.
Maybe large cell bees, in David's top bar hive, built less small cell size comb simply because the bees ran out of vertical space. Not because they couldn't construct it. They did construct about half the amount the Lusbees did. What do you think?
Barry's Lusbees drew out less small cell comb than either Joe's or mine did! Now that's a surprise for fully regressed bees ;>)
Thanks
Thanks Joe for the feral comb photo. Have you ever seen anything like it? Joe works with feral bees and runs a feral bee group at Yahoo. He also maintains a Ecological Beekeeping Site with lots of small cell information.
Thanks David for the photos. It's no small task to work a top bar hive and shoot each comb. Before you're done, there are many nosey bees, hot comb and a sticky camera. I hate it when I get my new digital camera gets sticky :>) David has some photos of his comb and top bar hive. That's a neat honey cow don't you think? And as BerkeyDavid, he's a frequent contributor at Beesource.
Thanks Barry for the photos. Barry runs Beesource, the super center of beekeeping sites. And he lets me bounce my wild and crazy ideas off him. Now there's a friend. Here are his comb details and top bar hive photos.

