Specimen
Habitat
MP-0008 / 0024 â Cyperaceae
Cyperus alternifolius auct. (accepted name: C. involucratus Rottb.)
Shurogayatsuri (JP)
A tall umbrella sedge of pond margins, its bracts spread like the ribs of a parasol.
Distribution
Native to Africa, Madagascar and the Arabian Peninsula; cultivated and naturalised in the tropics and subtropics, including southern Japan.
Habitat
Pond and stream margins, wetlands and cultivated water gardens.
Morphology
A tall, tufted perennial sedge with stout, three-angled culms 1â2 m high. At the apex a whorl of long, linear, spreading bracts forms an umbrella-like involucre, from which umbels of small spikelets arise.
Botanical notes
Widely grown as an ornamental of ponds. The name Cyperus alternifolius L. properly applies to a species of Madagascar; plants in cultivation and naturalised in Japan are generally referred to C. involucratus.
References
Taxonomy and distribution follow Plants of the World Online (Kew), YList (Yonekura & Kajita) and regional floras; CITES Species+ for trade status. Descriptions are provisional and are revised as specimens are verified.