This association includes species-poor freshwater marshes dominated by Bolboschoenus yagara or B. laticarpus, or both species occurring together. It occurs in the littoral zone of fresh water bodies such as fishponds and fish storage ponds with fluctuating water table. The substrate is usually acidic and nutrient-poor in stands of B. yagara, or slightly richer in stands of B. laticarpus, and can be flooded by up to 80 cm deep water, but at least for some periods of time the bottom is exposed. This vegetation type is most common in the Třeboň Basin and adjacent parts of the Bohemian-Moravian Uplands, but scattered localities are also found elsewhere in the Czech Republic.