In former times Juncus tenageia was a rather common species in various parts of the Netherlands. Now it has become very rare as a result of the lowering of the waterlevel and of manuring. Excavation of loam near Udenhout (province N.-Brabant) resulted in a new habitat for the species. It was evident that J. tenageia is only present when the excavated loam was flooded in the last winter or spring. A rising waterlevel in the vegetation season, as was the case in 1972, resulted in the absence of this species.