This vegetation type is dominated by Bidens tripartita or Persicaria lapathifolia, which often form dense species-poor stands up to 150 cm tall. It occurs on exposed fishpond bottoms, along the shores of water reservoirs, in fish storage ponds, on river banks and wet arable land. Most often substrate is loamy to clayey mud, in places with an admixture of sand, and typically also with high nutrient content. However, this vegetation may also develop on nutrient-poor sites, where stands tend to be shorter. It tolerates substrate desiccation, therefore it also occurs in regions with warm and dry summers. In the Czech Republic it is most frequent in fishpond areas, but it is also common elsewhere at low to mid-altitudes.