INTRODUCTION

Dutch elm disease (DED) is a vascular wilt disease caused by the fungus Ophiostoma ulmi sensu lato (O. ulmi s.l.). Disease incidence for O. ulmi s.l. is high, with infection rates near 100% within invaded areas. In the last century two worldwide DED pandemics have occurred, with the second one which started in 1972, still continuing. Without serious control measures the current destructive trend will prevail. Eventually, this will result in a complete decimation of mature elms across the northern hemisphere.

This CD-ROM represents an interactive approach to understanding DED and its control. In addition, information about other wilt diseases in elm and the use of this tree species in former and modern times is included. There are five sections:

• DED Cycle
• DED Control
• Epidemiology
• Value and Utilization
• Additional Wilt Diseases

Each section can be entered at two levels of understanding (basic-expert), with easy movement between the levels. The different sections comprise a number of related subjects connected by links. The information on the CD-ROM is illustrated with photographs, figures and video material. A reference list and a glossary of terms is included.

This unique CD-ROM provides an overview of the most recent data on DED for anyone interested in this devastating tree disease.