Flowering rush

Description:

The plant is a rhizomatous, hairless, perennial aquatic plant. Other than suggested by its English common name, it is not a true rush. It is native to Eurasia and grows on the margins of still and slowly moving water down to a depth of about 3 m. It has pink flowers. The plant has linear, pointed leaves up to 1 metre long, or more. The leaves are triangular in cross-section and arise in two rows along the base. They are untoothed, parallel veined and twisted. The inflorescence is umbel-like consisting of a single terminal flower surrounded by three cymes. The flowers are regular and bisexual, 2 to 3 cm across. There are three petal-like sepals which are pink with darker veins. They persist in the fruit. The three petals are like the sepals but somewhat larger. 6 - 9 stamens. Carpels superior, 6 - 9 and slightly united at the base. When ripe they are obovoid and crowned with a persistent style. Ovules are numerous and found scattered over the inner surface of the carpel wall, except on the midrib and edges. Fruit is a follicle. The seeds have no endosperm and a straight embryo. It flowers from July until August.

Habitat:

Butomus umbellatus is an aquatic plant that likes its roots submerged in mud or in still waters of the margins of ponds, lakes or natural swimming pools.

Notes:

Spotted on a flood plain of the Ijssel river in rural area of Deventer, Holland.