202 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 11 
Table I —Results op the Season’s Work in the Cleanup Areas 
Area No. 
Apiaries Examined 
Colonies Inspected 
Total 
American 
European 
Total Diseased 
Free 
Total 
Diseased 
1 
67 
21 
24 
41 
26 
2,327 
357 
2 
76 
28 
— 
28 
48 
1,811 
317 
3 
18 
10 
— 
10 
8 
385 
78 
Total 
161 
59 
24 
79 
82 
4,523 
752 
diseased apiaries found in the whole state in the previous two years 
of inspection service and only 7 of these in the three counties of which 
the three cleanup areas covered about one fourth. One fourth of 7 
would be an average of 2 for the entire cleanup area but that would 
not be a fair basis as each cleanup was started from one of the previous 
cases, so this number should be doubled. But 4 diseased apiaries 
known where there proved to be 79 shows how really inefficient the 
old method was and how hopeless the expectation of ever cleaning up 
any bad area, such as these proved to be, by that method. 
It would be foolish to say or to expect that these areas are “ cleaned 
up”—they are not—but the actual condition is now known. Every 
owner knows his problem and has the knowledge necessary to success; 
many are already clean, others are on the watch and the reinspection 
will be comparatively easy in most cases. All this is, however, pre¬ 
liminary to the real object of the present paper. 
In the inspection work one is frequently met by the statement that 
it is of no value to clean up foulbrood in the apiaries as long as the 
bee-trees cannot be inspected, as the disease will be redistributed over 
the area from this source. As bee-trees abound in a very large part 
of the honey-producing section of the state this seemed to be a prob¬ 
lem worthy of careful consideration and investigation. 
The writer was fortunate enough to be in the field while all the work 
was carried on in one part of area number 2, and tried to ascertain the 
source of each case of American foulbrood found in this district. The 
results were so striking and so at variance with the common belief as 
to the general means of spread of this disease that they have been 
plotted in Figure 1. 
We see from the chart that the primary infection occurred along the 
Wisconsin River. This infection is apparently of long standing as 
most of the apiaries in the immediate neighborhood have been entirely 
destroyed for some years past. Mr. S.’s case is typical. He pur¬ 
chased bees from Mr. A. many years ago. From 112 swarms at one 
time his apiary dwindled down until not a single swarm was left alive. 
Mr. S. lives beside the only bridge across the river for many miles 
