This work presents the results of studying (1990-1992) such wild oat species as Avena clauda Dur., A. pilosa M.B., A. bruhnsiana Grun., A. wiestii Steud., A. barbata Pott.; weedy species -A. sterilis L., A. fatua L. and A. ludoviciana Dur. The range of variability by agricultural traits has been shown and plant forms have been identified by such traits as earliness, dwarfness, productive tillering, resistance to lodging, crown and stem rusts, powdery mildew, tolerance to BYDV and other morphological characters. The author has defined parameters of interrelation between the duration of the vegetation period and its separate phases as well as between other agricultural and morphological traits.