September, 1907 



American ^ae Journal 



honey-board on the liive, and wrap an 

 old cloth around it. In warm weather 

 this is sufficient protection. However, 

 if the weather is cool and windy, I put 

 on a super and slip the hood down over 

 it. In mild weather the bees take the 

 food down in a few hours. I also use 

 this method when feeding in- the cellar, 

 of which I shall now speak. 



"A few years after my unsuccessful 

 experiment, I read in foreign papers 

 that bee-keepers water their bees in win- 

 ter. I concluded that if that disturbance 

 did not harm them ( I erroneously 

 thought that the cause of my failure 

 was due to the disturbance of this feed- 

 ing to the bees), no harm can come 

 from adding some honey or sugar to 

 the water, thus feeding the bees at the 

 same time. I now have a well-equipped, 

 dry bee-cellar, and had, in previous 

 years, fed the cellared bees liquid food ; 

 but never before near spring and after 

 a previous cleansing flight. I now con- 

 cluded to try ithis feeding before a 

 cleansing flight, in winter. 



"For this purpose I took, in the fall 

 of 1904, 3 colonies into the cellar, each 

 having about 10 pounds of honey. On 

 Feb. I, 1905, I gave each of these colo- 

 nies about a quart of a mixture consist- 

 ing of two parts clover honey and one 

 part water. The bees took this food in 

 about 6 hours, and remained very quiet 

 in the dark cellar. In 2 weeks this was 

 repeated with the same results. About 

 3 weeks later I gave each colony about 

 2 quarts in 2-quart jars. This time it 

 cooled before the bees had taken it all. 

 After the jars were about half empty, I 

 took them, heated the food, and then 

 returned it to the bees, when in about 

 24 hours the last drop was taken out of 

 the jars. 



"On March 28, 1905, these bees were 

 taken out of the cellar. They had brood 

 in all stages, and no sign of dysentery 

 noticeable. However, they had to be 

 fed once more during spring. But they 

 were the first of 91 colonies wintered, 

 to cast swarms. One of these colonies 

 swarmed on May- 28 — unusually early 

 for this locality. 



"Encouraged by these results, I pur- 

 posely placed 16 light colonies in the 

 cellar, in the fall of 1905. The amount 

 of honey present in these colonies varied 

 froin 10 to 12 pounds. The first feed, 

 consisting of 2 parts of white sugar and 

 one part of water, was given them on 

 Feb. 14. 1906. I gave each colony a 

 quart of this mixture. In about 2 weeks 

 another quart of sugar syrup was given 

 each colony. This time 2 of the colo- 

 nies refused to take the food, the re- 

 maining 14 colonies taking it in the 

 usual way. About the middle of March 

 the feeding was repeated, and at the 

 end of March once more. In all, these 

 16 colonies were fed about 145 pounds 

 of sugar syrup. Since about 1-3 was 

 water, the cost of wintering the iG colo- 

 nies was about 6 pounds of sugar and 

 II pounds of honey per colony. 



"On .\pril 2. 1906, these colonies were 

 taken from the cellar. The two colo- 

 nies which, after the first feeding, re- 

 fused to take more food, were found 

 very weak in number of bees, but the 

 other 14 colonies were in excellent con- 

 dition, and swarmed very early. Each 



of these colonies was in every respect 

 equal to any of the other 9^ colonies 

 wintered on combs of honey. Last fall, 

 I placed several exceedingly light colo- 

 nies in the cellar and began feeding 

 very early. I shall report the succjss 

 or failure next spring." 

 New Memphis, 111. 



The Cause of American Foul 

 Brood 



BY DR. G. F. WHITE, PH. D., 

 Expert in Bacteriology. 



For several reasons much confusion 

 exists as to the present status of our 

 knowledge of bee-diseases. It is hoped 

 that this circular will give information 

 which will to some extent clear up the 

 subject of American foul brood from a 

 bacteriological point of view. The 

 symptoms of this disease are given in 

 Circular No. 79 of the Bureau of En- 

 tomology, entitled. "The Brood Dis- 

 eases of Bees." American foul brood 

 is the prevalent disease in America. and, 

 judgmg from reports received from 

 Europe and from descriptions in Euro- 

 pean bee-journals and books, it is the 

 prevalent one there. There is another 

 diseased condition, which Cheyne ex- 

 amined, and to which we now refer as 

 "European foul brood." 



Wlien the author began his work on 

 bee-diseases, in the summer of 1902, 

 he observed, in combs containing Amer- 

 ican foul brood, in the dried remains of 

 the dead larvae, known as the scales, 

 a very large 'number of spores which 

 failed to grow when inoculated into 

 the media ordinarily used in the labo- 

 rator)'. It was clear, then, that these 

 spores are not Bacillus alvci, and that 

 this disease is not the "foul brood" of 

 Cheshire and Cheyne. The following 

 year the study was continued and a 

 medium was devised in which the spores 

 found in this disease will germinate. 

 This medium consists of an agar made 

 by following the directions ordinarily 

 used in the laboratory, with the excep- 

 tion that bee-larva: are substituted for 

 meat. By the use of this medium were 

 obtained pure cultures of the luicro- 

 organism which is found so abundant- 

 ly, in the form of spores, in the dried 

 scales of American foul brood. 



In reporting these findings the author 

 referred to this organism as "Bacillus 

 X." Further study was subsequently 

 made, and the species was given the 

 permanent name Bacillus larvae. The 

 description of this species may be found 

 in Technical Series No. 14 of this Bu- 

 reau. In his publications the author 

 has made no claim that Bacillus larvae 

 is the cause of American foul brood, 

 but has made the statement that it is 

 found to be present in all the samples 

 of this disease which have been exam- 

 ined by him. No inoculation experi- 

 ments were made, for the reason that 

 sufficient cultures in suitable condition 

 could not be obtained from any medium 

 then known. 



Since the media used in former in- 

 vestigations are not suitable for obtain- 

 ing cultures for purposes of inocu- 

 lation, in taking up the further study 



it has been necessary to devise a me- 

 dium which would be satisfactory in 

 this respect. Such a medium has been 

 discovered, and large amounts of the 

 culture suitable for experimental in- 

 oculations liave been obtained. This 

 medium is prepared and used as fol- 

 lows : Healthy bee - larv^ or young 

 pupae are picked from the coinb, -crush- 

 ed, strained through cheese-cloth, di- 

 luted with 20 to 50 times their volume 

 of water, filtered through ordinary fil- 

 ter-paper, and then passed through an 

 earthenware filter (the Berkefeld filter 

 is satisfactory) to remove any bacteria 

 which are present. The sterile filtrate 

 thus obtained may be filtered into tubes 

 or flasks and stored until needed. When 

 Bacillus larvae is to be isolated, a tube 

 of the ordinary agar of the laboratory 

 is liquefied and cooled to 45° or 50° C. 

 Then adout c.c. of the filtrate mentioned 

 above is added to it. A very small 

 amount of the decaying larvse affected 

 with American foul brood is then added. 

 The procedure from this point is as 

 usual in making agar plate cultures ; 

 these plates are afterward incubated. 

 When a large amount of culture is de- 

 sired for experimental purposes it is 

 convenient to use the ordinary agar 

 medium in large test-tubes to which 

 has been added, as above, about 2 c.c. 

 of the sterile larva? filtrate. These agar 

 tubes are then inclined and the surface 

 of the congealed agar is inoculated. In 

 no case should the larvK or filtrate reach 

 a high teiuperature. The object, of 

 course, is to obtain a medium which 

 contains the food constituents which are 

 afforded the bacteria in the living larv;e. 



Inoculation experiments have been 

 made by feeding to a healthy colony 

 the scales from combs which had con- 

 tained brood affected with American foul 

 brood. The result of the feeding was 

 that the colony became afli'ected by dis- 

 ease, the symptoms of which were the 

 same as those observed in the apiary 

 where American foul brood is found. 

 Like symptoius have been produced by 

 feeding scales which had been put into 

 ordinary meat bouillon, incubated for 

 twenty-four hours, and then heated to 

 65° C. for twenty minutes. 



On microscopic examination of the 

 decaying larvae dead from the disease 

 thus produced experimentally, the same 

 large number of spores and rods are 

 seen as when samples are examined 

 which are taken from an apiary affected 

 with American foul brood. From these 

 dead larvse pure cultures of Bacillus 

 larvae were obtained from plates, using 

 These experiments show that by the 

 feeding method the disease luay be pro- 

 duced and that the contagion is found 

 in the scales. The second experiment 

 tends to indicate the cause of Ameri- 

 can foul brood as found in the scales is 

 not killed by heat at 65° C. applied for 

 twenty minutes. 



Up to the present time there is no 

 authentic record of this disease having 

 been produced by e.xperiiuental inocu- 

 lations of pure cultures. 



Knowing that by the feeding method 

 the disease may be produced, pure cul- 

 tures of Bacillus larvae have been 

 mixed with sterile sugar syrup and fed 

 to healtliy colonies with the result that 



