Ophiostoma novo-ulmi is a fungal pathogen known for causing Dutch elm disease, which affects elm trees. This fungus spreads through the bark beetle, particularly the Scolytus species, which carries the spores from infected trees to healthy ones. The disease leads to the wilting and eventual death of affected trees, posing a significant threat to elm populations worldwide. Management strategies often include removing infected trees and controlling beetle populations to prevent further spread of the fungus.