heterogeneous, random distribution of variable-sized uredinia on single leaf (X) X acronym entity method_of heterogeneous, ordered distribution of variable-sized uredinia, with larger uredinia at leaf tip (Y) Y nearly immune, no uredinia, but hypersensitive necrotic or chlorotic flecks present (,) , very resistant, small uredinia surrounded by necrosis (1) 1 immune, no uredinia or other macroscopic sign of infection (0) I variable_of scale_of attribute moderately susceptible, medium-sized uredinia that may be associated with chlorosis (3) 3 Z Heterogeneous, ordered distribution of variable-sized uredinia, with larger uredinia at leaf base (Z) susceptible, large uredinia without chlorosis (4) 4 moderately resistant, small to medium uredinia often surrounded by Chlorosis or necrosis, green island may be surrounded by chlorotic or necrotic border (2) 2 0-8 Rust infection type