Professor Johanna Westerdijk and Dutch Elm Disease are inseparably connected. In the years between 1920 and 1930, Johanna and her team are responsible for the discovery and determination of Dutch Elm Disease and the fungi Ophiostoma novo-ulmi. This groundbreaking research is still the basis of our knowledge of Dutch Elm Disease. Besides her role in the DED research, Johanna Westerdijk was the first female professor in The Netherland. As a tribute, the organization SPORE made a wall painting on a building in Utrecht.