RT Journal Article SR Electronic T1 The Dutch Elm Disease in Europe Arose Earlier Than Was Thought JF Arboriculture & Urban Forestry JO JOA FD International Society of Arboriculture SP 281 OP 288 DO 10.48044/jauf.1990.062 VO 16 IS 11 A1 Holmes, Francis W. YR 1990 UL http://auf.isa-arbor.com/content/16/11/281.abstract AB In January 1922, Dina Spierenburg published a second article on Dutch elm disease (DED) but with a title identical to the first: “Een onbekende ziekte in de iepen.” Here she told of isolating a “Cephalosporiνm-Graphium” mixture from discolored wood in the growth layers of 1912 and 1913 of several small DED-infected, street-side elms in Renkum, The Netherlands, and in the layers of 1912-1915 of a large elm in Rotterdam. Her photos show that she had the same fungus as the one that Schwarz the same year was naming Graphium ulmi. Spierenburg’s distribution map for 1921 showed that DED was then already in all provinces of The Netherlands. If one accepts Belgian and French DED reports (not based on cultures), the epiphytotic center appears to have been near Antwerp. In view of later experiences with rates of DED spread, the European infestation appears to have begun about 1900 to 1905. World War I events therefore are quite unrelated to DED origin.