Racomitrium lanuginosum Woolly Fringe-moss

A dioicous, acrocarpous moss which is particularly characteristic of boulder fields and scree in the uplands. It can be a dominant plant species on mountain plateau forming a well-defined ecological community type called Racomitrium-heath. It usually grows on siliceous rocks but it is occasionally found on more base-rich rocks. Colonies are green, or greyish-green colour when moist but become very pale grey when dry. It is very desiccation-tolerant and, in a way similar to Syntrichia ruraliformis, the dry grey colonies recover rapidly to a fresh green colour when they are wetted. The long, white, coarsly-toothed hairpoints at the end of the somewhat curved leaves are conspicuous, particularly when plants are dry. On exposed alpine sites they may help to reflect harmful UV radiation. It is a Boreo-arctic montane species which is widespread in the uplands of wetern and northern Britain and found throughout Wales. In West Glamorgan it is is most commonly encountered on sandstone rocks in the uplands of the South Wales Coalfield but it also occurs sporadically on lower ground near the coast in Neath Port Talbot. Sporophyte capsules are occasional in spring.