In 1998 Juncus capitatus was found on three new localities in the province of Noord-Brabant. All three localities were former arable fields, where the eutrophicated top soil layer has been removed and pools have been dug out. The fast growth of perennials, tree-saplings and mosses on these spots forms a threat for the long-term establishment of the tiny pioneer species of the Nanocyperion communities. Active management will be necessary to preserve this species.