A life cycle takes approximately 2 years to complete. Black, white, water, willow, laurel, black-jack, southern red and turkey oaks are affected but not seriously damaged. The most diagnostic symptom produced by infected pines of Southern Fusiform Rust is the formation of perennial fusiform or spindle-shaped swellings on branches and main stems. Symptoms on oaks are relatively inconspicuous and require close examination of the lower leaf surfaces to observe yellow uredial pustules and black hair-like clusters of telia. The first indication of infection on needles appears as purple spots 4 to 10 weeks after inoculation.
Spots later turn yellowgreen.
Cup-shaped pycnia develop under epidermal layers in galled tissues 1 to 2 years after infection. The following year, aecia develop in galled tissues. Large numbers of aeciospores are produced, imparting a yellow color to infected stems. Aeciospores are wind-disseminated during February, March, and April, and infect leaves of susceptible oaks. Approximately 2 weeks after infection of oak leaves by aeciospores, uredia appear as pale-green spots on lower leaf surfaces.