VIEW ARTICLE

Susceptibility of Southern Oaks to Cronartium fusiforme and Cronartium quercuum. L. David Dwinell, Plant Pathologist, USDA Forest Service, Southeastern Forest Experiment Station, Forestry Sciences Laboratory, Athens, Georgia 30602; Phytopathology 64:400-403. Accepted for publication 9 October 1973. DOI: 10.1094/Phyto-64-400.

In a greenhouse study, 21 species of oaks were inoculated with aeciospores of Cronartium fusiforme and C. quercuum. Based on an evaluation of telia/cm², water and willow oaks were highly susceptible to C. fusiforme. Blackjack, cherrybark, bluejack, running, southern red, northern red, and turkey oaks were moderately to highly susceptible to C. fusiforme. Scarlet and black oaks were generally hypersensitive to C. fusiforme. Water oak was most susceptible to C. quercuum. Northern red and black oaks were also highly susceptible to C. quercuum, followed by bluejack, blackjack, southern red, and scarlet oaks. Northern red and black oaks were more susceptible to C. quercuum than to C. fusiforme. Water, willow, cherrybark, bluejack, running, turkey, and overcup oaks were more susceptible to C. fusiforme than to C. quercuum. The black oak group was much more susceptible to both pathogens than the white oak group. For several oak species, this is the first report of them as hosts of either C. fusiforme or C. quercuum.