Cirsium (Asteraceae) de Rona (Grisons, Suisse)
In 1972 and 1973, the following Cirsium species and hybrids were observed near Rona (Switzerland): C. acaule, C. arvense, C. helenioides, C. montanum, C. oleraceum, C. palustre, C. spinosissimum, C. vulgare, C. acaule x helenioides, C. acaule x oleraceum, C. helenioides x montanum, C. helenioides x oleraceum, C. montanum x oleraceum and C. helenioides x palustre. - Cirsium montanum was apparently never observed in Switzerland, but its presence in Rona does not extend very much its geographical distribution and agrees with its ecology. C. montanum x oleraceum is described as C. x braun-blanquetianum hybr. nov.