Plants with inflorescences are mostly in shallows near margins, in water to 35 cm deep.
Identified as C. multifructum rather than C. procerum because: leaves narrow, leaves floating rather than erect, inflorescence crowded.
Very few plants have inflorescences: grazing by swans and possibly swamphens means almost no flower spikes except in shallows near carpark, areas avoided by swans. Cut-off inflorescences are very common in amongst floating bits of plants.