Bryophytes under a moss “canopy” on the Stradch Mountain (Ukraine)

The aim of this work was to investigate the ability of some mosses to grow under a “canopy” of larger life-forms of the other moss species, because at the moment this subject is poorly studied. On the northern slope of the Stradch Mountain (Yavoriv District, Lviv Region, Ukraine) in a 100-year old Pinus sylvestris planting it was identified two moss species, gametophytes of which grew under a moss “canopy”: rare and the near threatened Buxbaumia viridis, which is in the Ukrainian and European Red-list books and a common species of Ukrainian bryoflora Plagiomnium rostratum. On the investigated site B. viridis grew exclusively on the ground adjacent to tree roots, with its gametophytes under the canopy of moss Dicranella heteromalla. P. rostratum occured freely on the ground or hidden under the “canopy” of wefts of Pleurozium schreberi, Rhytidiadelphus squarrosus, Rhytidiadelphus triquetrus, Thuidium tamariscinum or tufts of Polytrichastrum longisetum. Without moss “canopy” P. rostratum occurred only on quite shaded ground. On well-illuminated sites P. rostratum occurred exclusively being fully hidden. This study brings new information about the ecology of B. viridis and P. rostratum: the ability of their gametophytes to grow on the ground under a “canopy” of other moss species.