84 



AMERICAN BEE JOURNAL 



March 



The Sladen Two-Queen System 



By F. W. L. Sladen, Apiarist, Cana- 

 dian Department of Agriculture 



THIS system of management, 

 which was planned to meet the 

 conditions found in the vicinity 

 of Ottawa, Canada, and other nor- 

 thern localities where the swarming 

 season begins about four weeks be- 

 fore the principal honey flow and 

 lasts with great intensity for about 

 ten weeks, described in two of the 

 bee journals last year (Canadian 

 Horticulturist and Beekeeper, Octo- 

 ber, 1918; American Bee Journal, 

 April, 1919), has been further tested 

 and developed this year. 



The principal objects of this sys- 

 tem are to reduce the work of pre- 

 venting swarming and to increase the 

 number of bees raised for working 

 on the clover. 



The 1919 experiments show that 

 both these objects have been at- 

 tained, and that, although the season 

 was less favorable for spring breed- 

 ing in spring than usual, a somewhat 

 larger crop of honey was secured by 

 the regular colonies, the greatly in- 

 creased populations having over- 

 balanced a flagging in the work of 

 the bees during the requeening peri- 

 od. Means for reducing this idleness 

 are being studied. 



This system is part of a scheme to 

 render practicable and profitable the 

 management of outapiaries, requir- 

 ing only occasional visits in summer 

 and none in winter, in certain parts 

 of Canada where at present vast 

 quantities of nectar are going to 

 waste for" want of bees to gather it. 



The queen is caged or removed at 

 the beginning of the honey flow from 

 clover, and eight or nine days later 

 all queen-cells are destroyed except 

 two, one on each side of a division 

 then inserted, or two ripe queen-cells 

 are given. A special portico is fitted 

 over the front of the hive to enable 

 the two queens to mate without 

 meeting. Bees meet in supers above 

 the excluder. From the date the 

 bees are taken from the cellar at Ot- 

 tawa, about April 12, until the clover 







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Chart 3. Comparison during clover honeyflow of two hives on scales, one of them (continuous 

 line) containing two half colonies which were dequeened and united, raised two queens. 

 The other (dotted line), an ordinary or control colony, contained fertile queen. The latter 

 colony examined every week, had no active queen-cells after June 10. 



flow, which does not begin until about 

 June 22 (average of last five years), 

 the days are comparatively warm and 

 long,* so that two strong colonies are 

 developed from each hive by the 

 time the clover flow begins. Ordi- 

 nary colonies that have wintered well 

 begin to swarm during the dandelion 

 flow about May 24, but colonies man- 

 aged by this system are not strong 

 enough to swarm during the dande- 

 lion flow. By this means and by the 

 re-queening at the beginning of the 

 clover flow there is avoided the great 

 labor of lifting off every super, ex- 

 amining every comb containing brood 

 and finding and destroying all the 

 queen cells every week during the ten 

 weeks the swarming season lasts, 

 which so far has been found to be 

 the only satisfactory way to prevent 

 swarming at Ottawa.** The two 

 queens raise a much larger force of 

 bees for working on the clover than 

 ordinary colonies containing only one 



80' 



^Clover Flow bei^ixn. Ottawa 19/9, Ju. 



10 



iS 



Tcrcnit 



June 22 . 



SEPT 



Chart 1. 



Average weekly values of normal daily temperature, Ottawa and Toronto, and dates 

 clover flow beKJns. 



queen. Moreover, without further 

 manipulation, a moderate increase of 

 colonies is obtained and young 

 queens are raised for the next sea- 

 son's work. 



* At Ottawa there is a rapid rise in nonnal 

 daily temperature from 39 degrees on April 

 12 to 64 degrees on June 22, 25 degrees in 71 

 days, or about 2J^ degrees a week. During 

 the four weeks preceding June 22, the nor- 

 mal daily temperature is 61^ degrees, and the 

 average length of day 926 minutes. At Toron- 

 to, during the four weeks preceding June 10, 

 which a correspondent informs me is the date 

 at which the clover usually begins to yield in 

 that neighborhood, the normal daily tempera- 

 ture is only 56 degrees and the average daily 

 length of day 901 minutes. At Ottawa the 

 period of April 23 to June 22 is actually 

 about 2J^ degrees warmer than at Toronto 

 (see chart 1), due to the proximity of Toron- 

 to to the Great Lakes. But, apart from this, 

 in the north the breeding period preceding 

 the clover flow may be as warm as or warmer 

 than in the south, because it comes later, and 

 the north warms up quickly. Also the further 

 north one goes, the longer is the day during 

 the breeding period, not only because the 

 days are longer for the same date, but be- 

 cause this period is nearer the longest day. At 

 Ottawa the spring warms up so quickly that 

 the bees pass without any waste of energy 

 from the winter's rest to the almost full ac- 

 tivity of breeding. This, however, is a con- 

 tinental condition, and does not occur on the 

 Pacific Coast. Owing to the greater differ- 

 ence between day and night temperatures than 

 in the south and on the coasts, the days in 

 spring at Ottawa are actually warmer than the 

 normal temperature indicates. The day tem- 

 peratures also vary more from day to day, so 

 that there is much less dwindling weather. 45 

 to 65 degrees. Most of the days are either 

 so warm that the bees fly freely under what 

 would be called in England summer condi- 

 tions, or they are so cold that they remain 

 in the hives. 



These conditions furnish reasons for the 

 important fact that has come out very promi- 

 nently in these studies that the conditions are 

 more favorable for breeding up for the clover 

 flow in the northern half of the clover belt 

 than in the southern half. 



•* The great prosperity in the hive induced 

 in the spring and summer by the favorable 

 climatic conditions of the north combined 

 with the intense and long-continued honey 

 flows also helps to explain the intense and 

 long-continued desire to swarm, which is un- 

 known in the south. Giving plenty of ven- 

 tilation and room in the brood chamber can- 

 not be relied on to prevent swarming in the 

 north, and our experiments with the plan of 

 separating queen and brood have so far 

 proved unsatisfactory. 



