The Honeybee and the Beehive in Relation to Fire

The chief objective in fire Might control has been the eradication of hold-over cankers, since these cankers are known to be the principal source of primary inoculum in the spring. Consequently the possibility suggested by Rosen (11, 12Y that the fire bhght organism, Erwinia amylovora (Burr.) Bergey et al., may overwinter in the beehive has complicated the problem by introducing one more possible source of infection. Following the appearance of Rosen's first report in 1930, studies were begun in several States to determine the role played by the honeybee in the dissemination of the bacteria and to ascertain whether the bacteria overwinter in the beehive.* The findings from New York, Ohio, and CaUfomia detailed later, which are at variance with those from Arkansas, receive further support from this undertaking, an abstract of which has already been published (5), The fact that the honeybee is an important pollinating agent for fruit blossoms and that individuals from colonies of bees regularly visit fiowers at a time when they are highly susceptible to infection by the fire blight organism makes this problem a most important one. It must, however, be remembered that the worker bees which visit blossoms are not those which have had contact with contaminated material the year before, since the fife span of the worker is short. Normally no bee would be living in the colony at the time of visits to fruit blossoms which had been there the year before except the queen bee, and queen bees do not visit flowers. There remains, however, the somewhat remote possibihty that in some manner the queen bee might be involved in harboring the fire blight organism. Attention must also be directed to other places within the hive where the fire blight bacteria might remain, such as in honey or in other materials in and about the hive. These facts, then, center the investigation largely on the behavior of the bacteria when introduced into the hive, and it is on this point that special emphasis has been placed in this work. The chief aim of this investigation has been: (1) To determine the longevity of the fire bhght organism in the beehive when introduced through the natural channel in the food of the bees, but other aspects of the problem have also received attention, such as (2) the longevity of the bacteria in sugar solutions studied over a wide range of concentrations and temperatures; (3) the location of the bacteria in relation to the life-cycle stages of the insect; and (4) the extent OT