In the previous article, we made a detailed examination of reversing hive bodies, which is a method to maintain colony growth in the spring.
To review briefly, by early spring some clusters have ascended up under the cover, leaving empty combs below. Up under the hive cover, colony growth can stall. In a vertical hive design, the cluster more readily expands upward rather than downward. When wintering bees in double deeps or a deep and a pair of supers, beekeepers can reverse the hive bodies to help keep the colony growing unhindered. That places the deep (or the pair of supers) with the cluster in the lower position, right over the bottom board. The hive body of empty combs goes above the bees. Intuitively, the rising warmth from the bees themselves should help promote their upward expansion onto the empty comb.
During the practical, rugged field conditions in the apiary, reversing hive bodies is actually more flexible than its typical rigid description seems to suggest. Part of my frame-hive operation is in all medium supers (see Figure 1). I winter these colonies in three medium supers, a hive a little taller than a hive in double deeps. If the cluster occupies the two upper supers with an empty super below, then I “reverse” with just that one lower super, placing it alone above the other two with bees. Quite often, it seems the cluster expands up through that lone super fairly quickly. The bees appear between the top bars of the frames, a sign the colony will soon need another super of comb. From some other hive, whose cluster is small or just has spare supers on it, I find a super of comb for the growing colony.
By moving supers of comb, I try to accommodate all the growing colonies, as I move the clusters downward (see Figure 2). If one apiary has extra supers of comb, I load them on the bee truck, figuring I might need to “spend” them at another apiary. If not, and I have extra supers at the end of the work day, I store them where robber bees and especially animals (mainly raccoons) cannot get to them. (Raccoons are smart, strong for their size, and return relentlessly after tasting honey in comb, stored temporarily in the spring. Do not let them experience that first positive sweet reward.)
At this time in the spring, characterized by mild, variable nectar flows, interrupted by the cold, the bees do not normally build comb from newly secreted wax. Therefore, the bees will not build comb if given a super of foundation. Most importantly for the present situation, a colony in need of upward space, they will not expand onto to a super of foundation. On the contrary, expect the bees to chew the edges of the foundation, if given at this time. The bees are likely removing the wax for use elsewhere in the hive.
Analogous to reversing hive bodies with frames, colony management with top-bar hives has a technique meant to keep clusters growing onto empty combs (see Figure 3). Reversing hive bodies just changes the position of the cluster relative to its empty combs. When seen that way, top-bar-colony management has a technique analogous to reversing hive bodies. A (horizontal) top-bar hive’s front entrance wall restricts fast cluster growth in the spring like the cover of a (vertical) frame hive. Up in the vertical frame hive, and toward the entrance end in the horizontal top-bar hives, are both directions for rapid cluster expansion.
Against the front entrance wall, the top-bar colony can still grow, but slowly from the cluster’s side opposite the entrance of the hive (see Figure 4, left). During that time in the spring, empty combs are usually found in the rear of the top-bar hive (partly because the bees have been moving honey to the cluster on warmer days since fall, see below). After collecting about five empty combs together, I move the cluster toward the rear of the hive, which forms a space for the empty combs next to the entrances. The empty combs go between the cluster and the entrances (see Figure 4, right). Because I must handle individual combs, moving a top-bar cluster takes more time, compared to a frame hive, where the cluster resides in a hive body, and I move the combs as a unit. (The style of top-bar hive can make handling top bars and their combs slow and frustrating or fast and efficient. For example, the top bar ends should hang over the sides of the hive. That way you lift the top bar with just your fingertips, which automatically keeps the combs vertical.)
Not surprisingly, heat from a top-bar cluster should help it to expand, even when the hive is cold in the spring. More subtly though, the way the heat warms the adjacent combs is important, including how the bees behave in this warming microenvironment. Under the top bars of the hive, the warmth stays close and spreads horizontally, like from a low ceiling in a house.
The close-above top bars function as a wooden insulating barrier, and help to spread the heat into the honey bands at the upper regions of the nearby combs. When bees reoccupy adjacent and nearby combs, they move onto the upper regions of the combs, finding the honey in the bands, all in the warmth flowing directly from the cluster (see Figure 5). Bees acquire the opposite side of the comb by moving around its upper edges (see Figure 6), remaining in the warmth, unless it becomes too cold and they withdraw to the cluster.
In contrast to the low-ceiling effect from the top bars of a horizontal top-bar colony, the heat rises up between the combs in a vertical frame hive. In addition to heat loss by radiation, heat loss can probably leave on convective air currents, similar to heat loss from people sitting in a chilly room with a high vaulted ceiling. Except in the vertical-frame hive, the upward heat flow warms the adjacent comb just above the cluster, helping to prepare the way for the cluster to follow. Figure 7 shows a wide shaft of yellow warmth rising from a cluster in a single-comb top-bar hive. The upward heat flow from the cluster, warming the comb above, should be similar to that in a frame hive.
In the previous article, the colony shown in the former Figure 9 became a strong fast-growing colony. That was the observation hive colony in two tiers of medium frames above deep frames with extra space below. For a convenient reference, the left photograph of Figure 8 shows the winter cluster of that colony. Figure 8 (right) shows a closeup of the tight bee density of the insulating layer from the cluster.
I did not reverse the frames of this colony, figuring the bees would rapidly move downward (in an observation hive, three combs wide). That does not have to happen, but I want to see how the bees work out of that problem and not disturb them. (Therefore, I am not conducting typical bee management.) I wondered if more structures of the cluster would become apparent as the bees reclaimed the comb lower in the hive.
A transition is occurring among the photographs from a broodless cluster (or a small amount of brood) retaining its heat for survival to a cluster with a large brood nest and regulating its ….