Monitoring of Cypripedium calceolus (Orchidaceae) in the Adamello-Brenta Natural Park (Italy)

Abstract

The study reports data from a long-term monitoring (2007–2020) of a Cypripedium calceolus population (Orchidace-ae) in the Adamello-Brenta Natural Park (Trentino, North Italy). In the first four years, there was a gradual increase in the number of flowering stems. In 2010, a forest cut was performed and branches were left in place for three years. Number of orchid individuals decreased rapidly just after the cut, while after the removal of the branches in 2013 a recovery began. The proportion of stems with two flowers varied between 8.8% and 17.6%. Reproductive success was studied only in the first three years, varying between 5.2% and 19.7%. Several plants did not bloom because they were grazed by wild ungulates. As we observed that hikers and tourists collected some plants, we also recommend the surveillance of Cypripedium calceolus population during flowering period. Despite these multiple impacts, the studied population look to be viable. However, more attention should be implemented to future forest interventions.