Bul. 907, U. S. Dept. of Agriculture. PLATE |. 
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FUMIGATION OF CITRUS PLANTS WITH HyprRocyANic AcID. 
A, Fumigatorium used in experimental work, showing interior arrangement. 
B, Orchard citrus tree fumigated in the daytime and immediately afterward 
exposed to a hot sunshine; foliage completely destroyed. Other trees in the 
same grove, fumigated at an equal temperature but free from sunshine influence, 
were uninjured. 
