CONTROL OF ELM DISEASES IN NURSERY ELM PLANTINGS 
de UCU. Carber 
Introduction 
An investigation has been in progress in Illinois since 1931 to determine 
causes and possible control measures for the so-called "elm wilt." This term, used 
by nurserymen and others to designate any wilting of elms, regardless of cause, is 
so used for convenience in this paper. Several fungi have been found to cause "elm 
wilts"; namely, Coniothyrium, Cytosporina, Phoma, and Verticillium. A report on 
our tests of fungicides from 1931 to 1934 to control elm wilt was distributed in 
2935 as Biological Notes No. 4. 
In 1935 a reorganization of the experiments looking toward control became 
necessarye Of the ten plots that had been in use, 5 had to be abandoned, 3 because 
the trees had grown too large to be thoroughly dusted without power equipment, and 
2 because the trees were then too tall to be sprayed with the equipment available. 
In place of these 5 abandoned plots, 3 new plots were selected and planned 
to provide bon pereerte tests of dormant sprays and of new spray materials. The new 
plots, started in 1935, have been under treatment 2 years. 
The data given in the present report apply, as is indicated in the fore- 
going, eb 5 plots treated continuously from 1932 through 1936 and to 3 plots treated 
only for 2 years. 
Materials 
All experiments have been conducted upon American elms located in the 
midst of elm blocks being grown by nurseries as regular commercial production, in 
