This association includes open stands on well insolated, mobile screes, in which rock fragments are mixed with humus-poor fine soil. The dominant species, Galeopsis angustifolia, is accompanied by other short-lived plants, such as Microrrhinum minus. This vegetation type is typical of quarries, embankments and other anthropogenic screes. In natural conditions it preferentially occurs on upper parts of larger scree slopes where rock fragments tend to be smaller and mixed with fine soil.