Bryum radiculosum Wall Thread-moss

A small dioicous Bryum which forms compact, dark glossy-green tufts on old mortar on walls and on concrete and other similar calcareous substrates, often with Tortula muralis and other common wall species. It is similar to Bryum ruderale and Bryum subapiculatum but these species rarely if ever grow on walls. Nevertheless, safe identification requires microscopic study. It is widespread and fairly common in southern Britain and it has a scattered distribution in lowland areas of West Glamorgan, particularly along the south Gower coast. Both sexes are widespread and sporophyte capsules are common.