Report on dutch elm disease in Denmark
In July 1978, visual symptoms of Dutch elm disease, Ceratocystis ulmi (Buisman) C. Moreau, were seen on some elm trees in a short alley in a park in the city of Odense (island of Funen). The trees were of the species Ulmus glabra Huds. and approximately 60 years old. Tests, confirmed by kind cooperation of the Forestry Commission, Pathology Branch, Farnham, UK, have shown that the disease was correctly identified and that the pathogen was of the aggressive strain. Investigation showed the presence of bark beetles of the species Scolytus laevis Chap. only.
Immediately after the first visual symptoms were found and before the disease was finally confirmed, all trees in the alley, of which less than half showed symptoms, were destroyed. The whole city was searched for other cases of the disease but none were found. If the disease was confined to the now destroyed alley, the eradication attempt may have been successful. Careful checks will continue throughout the following year.
Sources
Plant Protection Service, Hellerup (1978-10)