Session

Mediterranean ruderal dry grasslands of the order Brometalia rubenti-tectorum are characterized by the dominance of medium to tall Mediterranean annuals, in particular grasses. They occur in anthropogenous environments in particular on abndonend fields but alto in clearings in the scrub or on sand dunes in natural situations. They are currentli classified in the class Stellarietea mediae (= Chenopodietea), a classa that includes the ruderal nitrophile vegetation. However, the position of this order in the claass Stellarietea is problematix. In fact Brometalia occur in much more natural conditions than other communities of Stellarietea and they are apparently much less nitrophile. They present instead a strong similarity with the infestant vegetation of wheat crops, which shares with Brometalia rubenti-tectorum a dry, non very nitrophile ecology. Infestant of crops are sometimes included in Stellarietea mediae and sometimes are considered a distinct class in it own. Papaveretea rhoadis . We propose to confimr the distinctiveness of Stipo.Trachynietea distachyae and include in it the two orders Papaveretalia rhoeadis and Brometalia rubenti-toctorum. A thorough study of this vegetation will require to move beyond Europe and collect relevés in the understudied regions of Middle East where this vegetation has its centre of distribution.