12 FAEMEES' BULLETIN 1713 



amount of American foulbrood. This is the only use recommended 

 for disinfecting solutions in connection with the treatment of this 

 disease. 



Super combs can be disinfected with a 20 percent formalin-water 

 solution — that is, 20 parts of formalin^ to 80 parts of water, liquid 

 measure. The combs to be disinfected should be free of honey. 

 They should be kept inmiersed in the solution at a temperature 

 of not less than 70° F. for at least 24 hours. At lower temperatures 

 sterilization proceeds much more slowly. In order that the solu- 

 tion may come in contact with all parts of the cells, after being 

 placed in the solution the combs should be agitated to dispel as 

 many air bubbles as possible. This can also be accomplished by 

 pouring the solution into the tank so that it rises slowly enough 

 to fill each cell completely. 



The 20 percent formalin-water solution may be used repeatedly 

 without much deterioration in strength. It is advisable, however, to 

 add formalin occasionally to maintain full strength of the solution. 



Formalin is unpleasant to work with, although not dangerous. It 

 is well for the operator to protect his hands with rubber gloves. 



Formalin-alcohol solution, formaldehyde gas, and chlorine also 

 kill the spores of American foulbrood without necessarily destroying 

 the combs. Formalin-alcohol solution, a patented article, is slightly 

 less effective than the 20 percent formalin-water solution and is 

 more expensive. Formaldehyde in gaseous form cannot be recom- 

 mended for treating American foulbrood combs. The use of chlo- 

 rine, although still in the experimental stage, has produced disap- 

 pointing results and, moreover, it is extremely dangerous to handle. 



TREATMENT BY STATE INSPECTORS 



Under most conditions inspectors are justified in burning every 

 diseased colony immediately, because such a colony constitutes a 

 menace to all healthy colonies in the vicinity. The maintenance of 

 such a serious nuisance as a colony containing American foulbrood 

 should not be tolerated. The best interests of the industry demand 

 the prompt disposal of all such colonies. 



When a State inspection force is applying- the area-clean-up 

 method for the first time, however, and when the incidence of the 

 disease is high, the use of the shaking treatment is sometimes justi- 

 fiable. The advisability of using it depends not only upon the 

 amount of disease in a particular apiary or area, but upon the char- 

 acter of the beekeeping, the kind of equipment employed, and the 

 facilities and experience of the beekeepers for doing the job. 



Where shaking is used in the first steps of an eradication program, 

 the State inspectors should give every consideration to the protec- 

 tion of healthy colonies. The establishment of temporary yards 

 where diseased colonies can be treated without endangering healthy 

 colonies is strongly recommended in this connection. These tem- 

 porary yards are not to be confused with hospital yards, which were 

 recommended at one time and with which many beekeepers are 



» Formalin or formaldehyde solution is an aqueous solution containing from 37 to 40 

 percent of formaldehyde gas. 



