Splits Are a Sound Investment

Bee Culture – March, 2007

by Walt Wright

This submittal is not a “how-to.” It’s oriented to the advantages, and specifically the whys of improvement in honey production. Some beekeepers are aware that last year’s starter colonies are this years best producers. It doesn’t matter whether last years starter was a package, natural swarm, or split, typically, the starter out-performs more established colonies in its second season. The improved production is sometimes attributed to the younger queen in the second year buildup. While that may help, it is not the major reason for improved production. If you are only interested in the real reason, you can skip to the last paragraph. We are going the long road around Robin’s barn to get there.

Just to insure that we are speaking the same language, a split to me is placing one to four frames of brood in a nuc (leous) box. Some beekeepers refer to equal division of colony assets as a split. I call each of those two units created a “divide.” Other beekeepers use the words split and nuc interchangeably. In my way of looking at it the split refers to action at the donor colony and a nuc is the result of that action. I’m nit-picking again.

The general advantages to making splits are manifold. A few spin-off advantages will be mentioned first. Putting the split/nuc to work drawing comb provides new comb for other uses, such as comb replacement and increasing drawn comb inventory for other purposes.

Splits (now a nuc) are beneficial in making up winter losses or increasing hive count. The whole concept of splitting/nucing is generating a new colony with available bees. You have but to supply a queen, feed, and boxes to generate a new colony. The resulting nuc has a head start over the purchased package of just bees. Not news.

Splits are the second most popular swarm prevention action – second only to hive body reversal. Based on the theory that “congestion causes swarming”, we are led to believe that removing a couple frames of brood relieves congestion. Any relief is very temporary. Do the arithmetic. Let’s assume a double deep brood chamber with the equivalent of eight frames of brood (more than eight makes it worse.) When two frames of brood are removed, you have reduced the potential population increase for that brood cycle by a mere 25 percent. The colony can cycle the whole worker brood volume in about 24 days (C.L. Farrar’s number). Disregarding brood cycles before and after taking the split, and the extensive population created by those, you have reduced congestion very little. The colony can make up the two frames pilfered in less than a week (25 % of 24 days.) When the before and after brood cycles are factored in, the effects of removing 2 frames are outgrown in a few days.

But the taking of splits IS fairly reliable swarm prevention. Why is that? You knew I couldn’t get by a discussion of swarming without putting in a plug for nectar management. The objective of NM is to open or remove the overhead honey reserve that limits brood nest expansion. When a split is taken from the top box, and substituted with empty comb, you have implemented the minimum requirements of NM. If you accuse the veteran beekeeper who practices splitting, of applying the principles of NM, expect an argument, at best, and don’t overlook the possibility of personal attack.

Having identified some of the desirable features of splitting, I must admit I don’t do it. My deeps divided in the middle to make 2-way nucs are collecting mud dauber nests in the loft of the bee barn. Nucs are impractical in my area. I have not learned to enjoy feeding bees. In this area, with a short spring flow, and 2 months of iffy field forage in mid summer, feeding of nucs is both expensive and time-consuming. They must be fed initially to get them up-and-running. About the time they get rolling, field forage trails off. For the summer doldrums, they must be fed more and more because they are building population and expanding comb for brood and storage.

Splitting/nucs are more practicable in more northerly locations where the spring and fall flows nearly merge in mid summer. Packages and other starters, including splits, can be expected to produce some surplus in those areas. Feeding is restricted to getting them started in the early season. Different ball game.

For increase in hive count, I prefer the post-harvest divide. My harvest time for spring honey is early summer. When evenly divided at that time of the season the production colony has ample brood and stores to support them through the summer doldrums. Its a good way to use partial frames of honey that cause extracter imbalance during extracting. With a reasonable fall flow no feeding is required. My way may be as impractical in the north where harvest is later, as splitting/nucing is here. The divide needs some time to get organized.

Having rounded Robin’s barn with miscellaneous notes, we can now close in on reasons why second year colonies out-perform more established colonies. It has to do with colony operations that change with colony age. In the first year colony motivation is establishment. To become established they must build enough comb to rear replacement bees and accumulate enough stores for wintering. Those objectives cause a separate mode of operations. Although modes of operation are not found in bee literature, you know what that means. Your laundry washing machine or dryer has several modes – selected by switch position. Depending on the objective of each use the machine can be switched to the appropriate mode to accomplish the objective for that laundry load.

The popular beekeeping literature has no reference to colony modes of operation. From the literature you could conclude that the colony is just waiting for forage to show up on the horizon. When forage is available, they go after it in a big way. This impression is inaccurate. Sometimes forage is available that they do not work. It’s not that the colony does not know it’s out there, but they forage to support the colony “needs” at the time. Those needs change with operational modes.

Back to the establishment operational mode of the bee colony: When the first year colony is doing its best to meet requirements for wintering they have several top priority activities at the same time. Building comb, rearing replacement bees, feeding the colony, and accumulating stores are all equally important to survival. Meeting those survival requirements in parallel causes a unique operational mode. As an example of that mode, the urgency of making progress induces them to build cells while using them. They will put brood or stores in cells that are barely started and build cell walls around developing larva or stores accumulation. That characteristic is unique to establishment.

Colonies three years old or more are typically well established by having their residence cavity filled with functional comb. When fully established each season is broken into different operational modes synchronized to the vegetative development of the area. In late winter the colony is dedicated to reproductive swarming. They stay in that mode until spring greenup, and change to a second mode to gear up to store winter rations. The second (intermediate) mode is dedicated to rearing house bees to support main flow storing and lasts for a worker brood cycle. When the house bees are ready to support “main” flow storing, the colony switches to the third operational mode of the spring season. In that storing mode, they are geared to store winter rations with maximum efficiency. Collection, curing and capping of available nectar is the main thrust of that mode.

The details of internal activities or colony operations are much too complex to report in this submittal. The generalities of the first and third year spring modes are provided above to set the stage for a discussion of second year differences. The second year colony has more flexibility in their modes of operations. If the second year colony that survives the winter perceives that full establishment was not accomplished in their first season, they can emerge from winter in the establishment mode. They can have wax making capability a full month prior to the new wax making (main flow) of the third year colony. However, if establishment was completed in the first season, the second year colony behaves much like third year colonies and doesn’t develop wax making capability until the main flow timing.

It’s easy to see how the above difference supports colony long-term survival, but there are other second year differences where improved survival are not obvious. There are likely other differences that have not come to my attention. Subtle differences could easily escape detection by observation. The two observations below were prominent enough to justify reporting them.

Nectar management induces supersedure. The second year colony typically supersedes earlier than the established colonies. Second year colonies supersede promptly at reproductive cut off, about three weeks prior to main flow. Third and subsequent year colonies scatter supersedure through the period, (both before and after), of start of main flow.

Second year colonies will store nectar at the top during the three week period prior to the main flow. That’s the period that overwintered colonies are rearing the nectar processors and wax makers for main flow storing. Third and subs. colonies add very little nectar at the top during that time. The forage collected is primarily used to feed the colony. It’s sometimes referred to by beekeepers as the “dearth” before the main flow, but there is ample nectar in the field. The second year colony gets a head start on production by storing a couple supers of nectar overhead before established colonies get out of their storage lull. And that’s the reason second year colonies are better honey producers than more established colonies.

Took a while to get there, but we made it.