Cyperus alternifolius subsp. flabelliformis
Synonyms
Cyperus flabelliformis Rottb.; Cyperus involucratus Rottb.
Family
Cyperaceae
Flora category
Vascular – Exotic
Structural class
Sedges
Conservation status
Not applicable
Simplified description
Distinctive sedge with almost rounded stems up to 80 cm, with many leaves at the top of each otherwise leafless stem, underneath an open flower head with many stalked clusters of flattened green spikes.
Distribution
Scattered in many parts of North island (usually close to habitation) and also in Christchurch.
Habitat
Margins of water bodies and in drains.
Wetland plant indicator status rating
Information derived from the revised national wetland plant list prepared to assist councils in delineating and monitoring wetlands (Clarkson et al., 2021 Manaaki Whenua – Landcare Research Contract Report LC3975 for Hawke’s Bay Regional Council). The national plant list categorises plants by the extent to which they are found in wetlands and not ‘drylands’. The indicator status ratings are OBL (obligate wetland), FACW (facultative wetland), FAC (facultative), FACU (facultative upland), and UPL (obligate upland). If you have suggestions for the Wetland Indicator Status Rating, please contact: [Enable JavaScript to view protected content]
FACW: Facultative Wetland
Usually is a hydrophyte but occasionally found in uplands (non-wetlands).
Detailed description
Rhizome short, stout. Stems to 60 cm high, stout, subterete. Leaves reduced to closely appressed, very pale brown basal sheaths. Involucral bracts many, ± equal, to 25 cm × 10 mm, > inflorescence, tips shortly acuminate. Inflorescence a compound umbel; rays many, to 8 cm long. Spikelets in small clusters at tips of rays, ± 4 × 2 mm, ovoid to linear-oblong, compressed, shining. Glumes densely imbricate, ± 2 mm long, ovate, obtuse, hyaline, white to light brown with green keel. Stamens 3. Style-branches 3. Nut ± ⅓ length of glume, trigonous, ovoid-ellipsoid, brown (Healy and Edgar, 1980).
Similar taxa
Similar to a small papyrus (Cyperus papyrus L.) and sometimes sold under that name, differing in the presence of persistent leaf-like bracts and upright flower stalks in Cyperus alternifolius subsp. flabellatus, rather than deciduous bracts and filamentous, drooping, mostly sterile flower stalks of papyrus.
Flowering
Summer to autumn
Flower colours
Green, Yellow
Fruiting
Summer to autumn
Life cycle
Deliberate planting or garden waste dumpings.
Year naturalised
1973
Origin
Africa
Reason for introduction
Ornamental plant
Control techniques
Not controlled in New Zealand.
Etymology
cyperus: From the ancient Greek name for sedge, kypeiros
Attribution
Prepared by Paul Champion and Deborah Hofstra (NIWA). Features description from Edgar and Healy (1980).
References and further reading
Champion P. et al. 2020. Freshwater Invasive Species of New Zealand 2020. NIWA publication. https://docs.niwa.co.nz/library/public/FreInSpec.pdf
Healy AJ, Edgar E. 1980. Flora of New Zealand, Volume III. Adventive Cyperaceous, Petalous and Spathaceous Monocotyledons. Government Printer, Wellington, NZ. 220 p.
Johnson PN, Brooke PA. 1989. Wetland plants in New Zealand. DSIR Field Guide, DSIR Publishing, Wellington, NZ. 319 p.