Schoenoplectus triqueter, commonly known as the triangular club-rush, is a species of sedge which lives in temperate Eurasian wetlands, on muddy shores and river margins.

Because of its tolerance of salty habitats, it is considered a halophyte, but plants which were subjected to a high salinity level (10 parts per thousand) in an experiment were noticeably stunted.

The plants subjected to a salinity level of 10 ppt had their growth noticeably stunted relative to the control sample.

[5] Another study, in Punjab, found that, in general, the length of the plants' roots consistently increased as the salinity of the soil was raised.

[8][10][3] The last known English population, on the River Tamar, died in 2012, but the species has been successfully re-introduced at ten sites.

[11] In North America, S. triqueter has been introduced in and around the lower Columbia River tidal region, where it is known to produce fertile hybrids with S.