90 Bee-lieeping in Victoria. 



live bees from the dwindling colonies differ in any way from bees of 

 normal colonies in districts unaffected. If the dwindling takes place 

 during midwinter the queen and the last hundred or so of bees perish 

 from cold ; when it occurs in spring, the bees and queen swarm out and 

 join some other colony when a point of numbers is reached from which 

 the colony could no longer recover. The queens of colonies which 

 dwindled in this way, when introduced to normal colonies in an unaf- 

 fected locality, do not reproduce dwindling in succeeding seasons, and 

 the combs from which the bees disappeared in no way affected other 

 br-es Avhich were put on them. 



During the spring of 1909, and again in 1912, heavy losses of bees 

 were experienced in the country near the Grampians, but not in the 

 scrub country on and inside the ranges. In both 1909 and 1912 there 

 was a dearth of pollen in the preceding autumn, followed by a honey- 

 flow from ironbark eucalypts, E. leucoxylon and E. sideroxylon. The 

 former is known by diff'erent names in different localities, such as white 

 ironbark. bluegum, whitegum, and spotted box. The latter is every- 

 where called red ironbark. Both are winter bloomers, and secrete 

 nectar very freely, but produce no pollen for bees. 



It has been suggested that the abnormal activity of the bees during 

 a period when they should l3e semi-dormant, which is caused by the 

 flowering of ironbarks, causes the premature wearing out of the 

 workers, and there seems to be some force in this contention. The 

 opposition to it is, however, the fact that when the tree variously known 

 as cabbage gum, bastard box, peppermint, &c., flowers during the 

 winter months, bees work freely on it and come through strong. This 

 tree, however, produces pollen freely, and, while but little brood can be 

 reared owing to low temperatures, the nitrogen withdrawn from the 

 body of the bee by the secretion of the enzyme which is necessary for 

 the changing of the nectar into honey, is continuously replaced by 

 the consumption of pollen foimd on the blossom from which the nectar 

 is gathered, and thus the vigour and vitality of the bee are maintained 

 when gathering from pollen-producing blossoms, but impaired when 

 working on flowers producing nectar only. 



Dr. Kramer, a well-known Swiss authorit3\ states that sugar syrup 

 (which contains no nitrogen) fed to bees and extracted contained the 

 same amoimt of nitrogen as pure honeJ^ The nitrogen was added out 

 of the bee's own organism. " That," Dr. Kramer says, " explains why 

 after being fed sugar, bees are so eager for pollen, also why bees rapidly 

 become enfeebled upon being fed sugar when no pollen or substitute is 

 available " {Gleanings in Bee-culture, Dec. 15, 1912, page 817). 



As bees do not obtain pollen from ironbark blossoms, a winter flow 

 from that source is the ef|uivalent to heavy sugar feeding with a lack 

 of pollen at the same time, which, as Dr. Kramer further on in the 

 same article says, " so rapidly decimates the colonies." 



Pending the collection of further data on this subject, and the dis- 

 covery of a means of supplying nitrogen artificially, beekeepers in 

 localities liable to this trouble will be well advised to remove their 

 colonies to some other locality during the " off year " preceding the 

 blooming of the ironbark. 



