A REPORT ON TESTS OF FUNGICIDES 
FOR THE CONTROL OF ELM DISEASES IN NURSERIES 
de Ca Carter 
SINCE 1931 tests have been conducted to determine whether or not 
certain spray and dust materials commonly employed in the prevention 
of infection by fungus diseases would be effective in reducing the 
amount of infection occurring in growing elms under nursery conditions. 
For the information of nurserymen and others, the results obtained in 
these tests are presented and preliminary recommendations for their use 
are suggested. 
Materials and Methods 
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Throughout, all tests have been made with the cooperation of the 
owners upon seedling American elm stock. Test plots have been set apart 
in the midst of blocks of trees being grown in the usual manner for the 
usual marketing, and the conditions under which all tests have been made are 
those which normally obtain in the commercial production of trees. Ten plots, 
utilizing for test and check purposes nearly 14,000 trees, have been used in 
these tests, 
In general the plan has been to arrange the plots so as to compare 
the use of a fungicide with its non-use, and in nearly every case to test 
also the value of pruning out diseased material, alone and in combination 
with a fungicide, 
The fungicides that have been employed are representative of those 
that have been found effective in orchards. The fungicidal chemicals are 
only two, copper and sulfur, copper being applied in the form of Bordeaux 
mixture and sulfur in two forms, as a dry dust applied directly to the trees 
and as a spray in which sulfur dust (called wettable sulfur) is suspended 
in water by mixing. The exact materials used in these tests are as follows; 
1.--Bordenux mixture, We have used a dry preparation of copper 
sulfate and lime prepared by the Corona chemicnl division of the Pittsburgh 
plate glass company. It needs only to be mixed, as received, with varying 
amounts of water to furnish Bordeaux mixtures having equal weights of its 
ingredients, "4-4-50," "5-5-50," or similar formulae depending only upon the 
amount of water used, 
2e--Koloform, A sulfur dust of the wettable type manufactured 
by the Niagara sprayer and chemical company for use as a sulfur spray. 
Agitation of the dry dust in water mixes it with the water so that it can 
be applied as a spray. 
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