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public or private control agency. This is often unwise, since the desire to 
empire build usually enters the scene and the decision of the agency is not 
always the correct one from the standpoint of disease control, conseivation, 
or public welfare. Since there are a few cities in which progress is ap- 
parently being made in slowing the spread of Dutch elm disease, I have 
attempted to evaluate several types of programs. I have also theorized on 
the point that similar, and possibly better, results could be obtained by a 
diligent sanitation program and no spraying. It is possible that indiscrimi- 
nant spraying has, besides destroying wildlife, increased the rate of transit 
of the disease-causing fungus. 
I. No SPRAYING—No To INCOMPLETE SANITATION. In some communities 
flanked by Dutch elm disease, the rate of infection is slow and a few trees 
are lost annually. No spray or sanitation program is attempted in these 
communities. The accumulated dead trees possibly serve as reservoirs for 
the fungus and breding sites for the beetles, thus enhancing the chance for 
an extensive outbreak. However, the fact that some trees are removed to 
satisfy the esthetic sense aids in reducing this hazard. In these instances 
biological controls, since they are not destroyed by insecticides, may be re- 
sponsible for the minor rate of infection. 
II. PARTIAL SPRAYING—PARTIAL SANITATION. In some localities partial 
control programs are followed. Trees along parkways, parks, and possibly 
other city property are sprayed. Dead trees in the same areas are removed. 
However, private property is not necessarily subjected to the same practices 
and little or no trimming of partially dead trees is attempted. Spraying 
ranges from one dormant coverage of D.D.T. to two applications, the second 
in the fall. Only a few communities use one or two coverages of methoxy- 
chlor instead of D.D.T., since methoxychlor is about three times more ex- 
pensive. The fact that methoxychlor is only one thirty-fifth as toxic to 
robins, and possibly other wildlife, fails to outweigh the economies involved. 
These programs have not proved satisfactory. 
III. ENFORCED SPRAY PROGRAM AND SANITATION. Other communities, rela- 
tively few in number, attempt extensive community-wide control programs. 
In these areas a block-by-block survey of the entire tree population is made 
at least twice during the summer by trained personnel. Sanitation and 
spraying are used throughout the community. Ordinances require citizens 
to remove dead or diseased trees from private property. This program has 
had some success and apparently slows the rate of fungus spread. However, 
small numbers of elms still die each year. The results, in many ways, re- 
semble those in communities mentioned earlier where no spraying is done 
and the disease still fails to reach extensive proportions. 
The communities indicating success with spray-sanitation programs were 
those that started early, before Dutch elm disease became well established. 
In areas where the disease is already causing high losses, similar success 
appears unlikely. 
IV. No SPRAYING—SANITATION ONLY. A fourth method of attack is used 
in a few areas; however, it appears to be gaining favor. This is an all-out 
Sanitation program without spraying. In this program an ordinance is usu- 
ally necessary to enforce the removal of dead trees and pruning of diseased 
trees on private property. This program has not been in effect long enough 
for its results to be recognizable. However, the logic behind it appears rea- 
sonable and most desirable from the standpoint of wildlife conservation. 
This program has been adopted by DeKalb, Illinois. Similar practices are 
