Oak wilt is one of the most destructive tree diseases in the U.S. and is killing oaks in Central and West Texas at epidemic proportions. It has been confirmed in 76 counties in Texas.
It is an infectious disease caused by the fungus Bretziella fagacearum, which invades and disables the water-conducting system in oaks. All oaks (Quercus spp.) can be infected by the fungus.
Oak wilt management
The successful management of oak wilt depends on correct diagnosis and an understanding of how the pathogen spreads between different oak species.
Red oaks play a critical role in the spread of oak wilt through the formation of fungal mats. Sap-feeding beetles pick up spores from these fungal mats and carry them to fresh wounds on other oaks. This is how new disease centers are started.
Live oaks grow from root sprouts and have vast, interconnected root systems that allow movement of the fungus between adjacent trees. The average rate of spread through root connections is 75 feet per year.