Ecological studies on the serpentine endemic plant Cerastium utriense Barberis

Cerastium utriense Barberis (Caryophyllaceae) is an endemic plant growing on ultramafic outcrops in northwestern Italy. Despite its great phytogeographical importance, little is known about its ecological requirements and environmental range. Thus, the main objective of the present work was to examine and clarify these aspects. On the basis of a preliminary survey on its range, 28 plots were sampled, and Ellenberg ecological indices of the flora growing with C. utriense were defined. Furthermore, on the basis of the floristic diversity and physical, chemical, and biological properties of the soils, 10 of these plots were selected and more closely investigated. This preliminary study characterized C. utriense as a strictly Ni-excluding serpentinophyte with no apparent relationship with typical chemical characteristics of serpentine soils. On the contrary, the species showed a direct association with physical traits typical of serpentine substrates.