This section is from the collection of "Booklets on Bee Managements", by Various Authors. See also: Hive Management: A Seasonal Guide for Beekeepers.
Queen supersedure is usually less evident in two-queen than in single-queen colonies. This occurrence takes place because when one queen begins to fail and thus produces less queen substance, which is the chemical that inhibits queen cell building, the other queen is still producing an adequate amount of the substance for the whole colony. Either the top or bottom unit then goes queenless, but the bees do not usually build cells.
Where the two-queen system is practiced in the larger commercial operations, re-establishing second queens in colonies that lose one queen is uneconomical. Proportionately too much time is required for a small percentage of the colonies. For those smaller operators who wish to replace lost queens in two-queen units, they must again start the two-queen system from the beginning.
Swarming is not a problem when good queens are maintained in broodnests and space for brood expansion and timely manipulations stimulate honey storage. If the colony is allowed to swarm, the loss of bees is considerable. The wings of both queens should be clipped. If the colony attempts to swarm, both queens may be found in the lower brood nest. One may be returned to the upper broodnest when the conditions that caused the swarming have been corrected.
The best way to deal with such colonies that have shrunken queens is to make a "shook swarm" with one queen on a new set of combs. The other queen, with all the brood and adhering bees, can be set to one side to allow many of the field bees to drift back to the original hive location. When both queens are again expanded and laying normally, the hives can be recombined in a manner suitable to the stage of the honey flow or used to make more colonies.
To make increase from two-queen colonies is not a good policy because the advantage of large pollen reserves for wintering, characteristic of two-queen colonies, may be lost. If conditions are favorable for abundant pollen storage, the two-queen organization can be retained to the end of the honey flow. Such colonies can be wintered as double colonies by removing the separating queen excluder and by placing at least 60 pounds of honey in dark combs above the lower broodnest. An inner cover with the escape hole closed or screened should separate the top and bottom broodnests. The bottom board entrance should be reduced or closed, and a single 1-inch auger-hole entrance used for each of the separated colonies. The winter clusters will mutually benefit from heat radiated through the separating inner cover.
Strong nuclei or one-story divisions with young queens may be overwintered above strong colonies similar to the overwintering of double units for increase described above. The purpose here, however, would be to simply overwinter one extra queen for each two-queen colony and enable the beekeeper to start his two-queen system without purchasing new queens in the spring. This is a dependable means of overwintering extra queens with less risk than a queen "bank" system.
Overwintering losses are virtually nonexistent when using the two-queen system. When losses do occur, they are usually in the early spring when large populations may starve if insufficient winter honey supplies were not left with the colonies in the fall to compensate for more intense winter brood rearing. Larger populations, larger pollen reserves, and resultant use of more honey in brood rearing dictate that the beekeeper leave 90 to 100 pounds of honey in the fall to carry the colony through until settled warm weather in the spring.
In the spring a weak colony may be set above a good colony in the manner used to organize a two-queen colony (division with an excluder beneath the weak colony in place of the inner cover). Unless a good spring nectar flow is in progress, the bees of both colonies should be gorged with sugar sirup when they are set together. When the weak colony has a good queen, some bees from the lower colony will move up and permit this queen to expand brood rearing. When it has a poor queen, nothing is lost as would be the case if brood or bees from a good colony were taken to strengthen a weak colony.
The two-queen system of colony management is based on the principle that honey production per unit number of bees increases as the population increases. Strong colonies not only produce more honey but they do it more efficiently than less populous colonies. The beekeeper gives more attention to queen quality than with most other systems of management. Two-queen colonies have a large winter pollen reserve, as much as 300 square inches more stored pollen, enabling colonies to raise more young bees during the winter.
Less hive equipment is needed to produce a given crop of honey. than is customary for single-queen management. Standard 10-frame hive equipment has limitations for two-queen management, however.
Key manipulations for two-queen management:
1. Build maximum populations in overwintered colonies by feeding pollen supplement in early spring.
2. Work the winter upper flight entrances gradually to the bottom.
3. Introduce second queens to divisions placed above inner covers with escape holes screened 2 months before the major honey flow. Divisions have auger-hole entrances.
4. Substitute queen excluders for division boards 2 weeks after introduction of the new queens.
5. Reverse brood chambers within each brood nest at 7- to 10-day intervals until about 4 weeks before the expected end of the flow.
6. Reunite to single-queen status after the bulk of the crop is removed.
(7) Dunham, W. E. 1953. The modified two-queen system for honey production. Amer. Bee T. 93: 111-113.
(2) Farrar, C. L. 1937. The influence of colony populations on honey produc tion. J. Agr. Res. 54: 945-954.
(3) -. 1953. Two-queen colony management. Amer. Bee J. 93: 108110, 117.
(4) -. 1958. Two-queen colony management for production of honey.
U. S. Dept. Agr., Agr. Res. Serv. ARS-33-48, 9 pp. Rev.
(5) Holzberlein, J. W. 1953. Getting started with two-queen management.
Amer. Bee J. 93: 114-115.
(6) Miller, L. F. 1953. Crop insurance with two queens. Amer. Bee J. 93:
113-117.
(7) Moeller, F. E. 1961. The relationship between colony populations and honey production as affected by honey bee stock lines. U. S. Dept. Agr. Prod. Res. Rpt. 55, 20 pp.
(8) -. 1962. Nosema disease control in package bees. Amer. Bee J.
102: 390-392.
(. 9) - and Harp, E. R. 1965. The two-queen system simplified. Glean.
Bee Cult. 93: 679-682, 698.
(10) Peer, D. F. 1969.. Two-queen management with package colonies. Amer.
Bee J. 109: 88-89.
(11) Schaefer, C. W., and Farrar, C. L. 1946. The use of pollen traps and pollen supplements in developing honey bee colonies. U. S. Dept. Agr. Cir. E-531, 7 pp. Rev.
(12) Walton, G. M. 1974. The single-queen and two-queen systems of colony management under commercial beekeeping conditions. J. Roy. New Zeal. Hort. (2): 34-43.
 
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