Of all types of tree diseases, fungi are the most damaging to our forests. Fungi are simple plants which are incapable of making their own food and must take it from a host organism. There are fungi which attack almost every part of a tree, including leaves, buds, stems, roots, and the inner circulatory system. The single most destructive disease of pines in South Carolina is fusiform rust. This fungus attacks most of the southern pines and loblolly pine is extremely susceptible.
Fusiform rust creates swellings or galls on pine stems and branches.
These galls grow as the infection spreads, killing branches and weakening stems. As these spores are blown by the wind, they land on and infect young, succulent oak leaves. Certain changes occur on the oak leaves and new spores are produced. These new spores are carried by the wind to re-infect pines, starting the cycle again. Other fungi cause other diseases.