Pilularia globulifera. Pillwort.

Life-form & Growth Form:

Hydrophyte/hemicryptophyte. Herbaceous perennial. Rhizomatous, rhizome far-creeping.  

Flowering period: 

June to August. 


Shallow margins of lakes, canals, ponds and slow-flowing rivers. Wet grasslands. Submerged for at least part of the year. A bare wetland margin specialist, therefore some poaching and waterside vegetation grazing by livestock beneficial.  


Historic lowering of water levels within Lough Neagh. Eutrophication of lough & river water through agricultural run-off. Loss and fragmentation of marginal wet grasslands as land drained and reclaimed for agricultural use. Under-grazing, leading to encroachment of taller wetland forbs and scrub.  

Static distribution map:
Pilularia globulifera
Pilularia globulifera
For an interactive map follow this link to the BSBI webpage