Why are many of our oaks dying? It's likely due to a syndrome called Oak Decline. There's an upcoming discussion on it. Sign up here:
You can also learn about it on our own page: https://www.arlingtonva.us/Government/Programs/Sustainability-and-Environment/Trees/Tree-Care-and-Removal/Oak-Decline
In recent years oaks in the white oak group, such as chestnut oak (Quercus montana) and white oak (Quercus alba), have started dying in significant numbers. This page lays out potential causes, what local governments are working on, and tips for tree owners.