Thirty-year invasion of the alien moss Campylopus introflexus (Hedw.) Brid. in Poland (East-Central Europe).
Campylopus introflexus is the only invasive moss listed among the 100 most prominent alien invaders in Europe. The present study shows dot distribution maps (at 10-years intervals from its introduction in 1986 to the present) and discusses the dynamics of its invasion, altitudinal distribution and ecological preferences. During the 30 years of its invasion, C. introflexus has spread widely throughout Poland and is currently known in 248 locations. A total of 93.1% of these are below 300 m a.s.l., and the maximum altitude is 780 m. With the passage of time since its first appearance this alien moss has occupied larger numbers of substrates and habitats. Currently C. introflexus is a component of 34 plant communities belonging to 18 habitat types. The most invaded habitats include young forest tree plantations and mature managed forest developed from old plantations (Pinus sylvestris woodland). This moss is frequently found in acidophilous semi-natural forests and inland dunes with Corynephorus and Agrostis grasslands, boggy woodland, dry heaths, and ruderal habitats. Although 30 cryptogam species were found in tufts of the alien moss, there is no characteristic species composition that constantly accompanies its presence.