Pillwort Pilularia globulifera

Status Amber - Vulnerable and Near-Threatened
Best Time to See

This tiny plant is a type of creeping fern. It is hard to spot because it has thin, grass-like leaves and often grows with water grasses or small rushes. The ‘pills’ are tiny round spore cases at the bases of the stems.


It can still be found at a number of sites scattered across Britain, but is internationally threatened, as it is declining across its whole European range.


Muddy ponds and places that are underwater in winter but dry mud in summer, typically near the edges of small field ponds where livestock graze.


Classified as Near Threatened.

Key threats

Water pollution, particularly by fertilisers, which encourage the growth of coarse plants. The decline of cattle grazing and the resultant loss of trampling; drainage; the ploughing of old pastures; and invasion by the vigorous non-native water plant New Zealand pigmyweed (Crassula helmsii).