Contributi allo studio dei Sedum della serie Rupestria Berger (Crassulaceae) dell'Italia nord-occidentale. I. Prime segnalazioni di S. montanum Song. et Perr. subsp. orientale 't Hart per il Piemonte

The author reports the presence of Sedum montanum Song. et Perr. subsp. orientale 't Hart in Piedmont. He shows the known distribution area by making a distinction between obsviously anthropical stations and populations wich are well established in the native communities. In order to help with its identification, a synoptic chart is then illustrated which shows the specific charatcteristics of S. montanus subsp. orientale and those of others taxa which are morphologically similar to it: S. montanum Song. et Perr. subsp. montanum, S. rupestre L. subsp. rupestre and S. rupestre L. subsp. erectum.