This association includes 0.5–2 m tall scrub of Pinus mugo, which locally covers extensive areas on nutrient-poor acidic soils in the subalpine belt of the Krkonoše Mountains. The canopy can be open or closed. Near the alpine timberline, it may contain stunted individuals of Picea abies or Sorbus aucuparia. The herb layer is species-poor with acidophilous grasses such as Avenella flexuosa, Calamagrostis villosa and Nardus stricta, dwarf shrubs such as Vaccinium myrtillus and V. vitis-idaea and acidophilous dicot herbs. In the Krkonoše Mountains the altitudinal belt in which this vegetation type is continuous ranges from 1230 to 1500 m a. s. l., but small patches can occur on avalanche tracks as low as 1050 m. In the Czech part of the Šumava Mountains this association occurs as azonal vegetation, forming small patches on talus slopes at altitudes of 1080–1360 m. Plantations of non-native Pinus mugo in the Hrubý Jeseník and Králický Sněžník Mountains are floristically and physiognomically similar to the natural stands of this association.