Shoots are up to 5 mm tall. Mature plants have an expanded leaf base which sheaths the stem and contracts abruptly to a leaf blade which is long and narrow, rather wavy and minutely toothed. Leaves are 2 to 2.5 mm long. Capsules are very rare.

T. cylindricus grows in acidic habitats, and is often abundant in stubble fields. It also grows in sand pits and gravel pits, on the banks of streams and rivers, disturbed roadsides, and sometimes on seasonally flooded ground at the edge of lakes and reservoirs.

All year round.

Widespread and fairly frequent in Britain.

Fairly frequent in Leicestershire and Rutland.