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Scientific Name
Cyperus teneristolon Mattf. & Kuk.
Synonyms
Cyperus transitorius Kuk.Kyllinga pulchella Kunth.
Family
Cyperaceae
Common Names
cyperus
Origin
Native to eastern and southern Africa.
Cultivation
Not deliberately cultivated in Australia.
Naturalised Distribution
This species currently has a very limited naturalised on the central tablelands in New South Wales (i.e. it is naturalised along Yosemite Creek near Katoomba in the Blue Mountains).
Habitat
In Australia it has so far only been recorded in disturbed sandy soils beside a small creek (in warmer temperate regions). Its native range, and naturalised populations in other parts of the world, suggest that it prefers highland areas with soils that are sandy and poor in nutrients.
Habit
A slender long-lived (i.e. perennial) plant with upright (i.e. erect) flowering stems usually growing up to 50 cm tall, but occasionally reaching 80 cm in height. It also spreads laterally via long creeping stems (i.e. stolons) that root at the joints (i.e. nodes) and creeping underground stems (i.e. rhizomes).
Distinguishing Features
- a long-lived sedge spreading via long and slender creeping stems.
- its slender upright flowering stems (up to 45 cm tall and about 1 mm thick) are triangular in cross-section.
- its leaves are borne in a cluster near the base of the plant.
- its seed-heads have 3-5 large leafy bracts below them that may be mistaken for leaves.
- these seed-heads are made up of one to several dense clusters of brownish-green flower spikelets.
Stems and Leaves
The upright (i.e. erect) flowering stems (i.e. culms) are triangular in cross-section (i.e. trigonous) and do not have any joints (i.e. nodes). They are smooth and hairless (i.e. glabrous) and relatively slender (about 1 mm thick).
The leaves are borne in a cluster near the base of the plant and consist of a sheath, which clasps the stem, and a spreading leaf blade. The bright green leaf blades (1-3 mm wide) are very narrow (i.e. linear) with pointed tips (i.e. acute apices). They are hairless (i.e. glabrous) and have entire margins.
Flowers and Fruit
The seed-heads (i.e. inflorescences) are borne at the tips of the stems and are more or less oblong to egg-shaped (i.e. ovoid) in outline (6-10 mm wide). They consist of one to several dense clusters of flower spikelets that are subtended by 3-5 leafy bracts. These long and narrow (i.e. linear) bracts are often mistaken for leaves and are often bent downwards (i.e. reflexed). Each of the small flower spikelets (3-5 mm long) is somewhat flattened and contains 2-4 tiny florets. The florets are made up of a tiny bract (i.e. glume), a style that divides into two branches near its tip, and three stamens. The bracts (i.e. glumes) are green with dark purplish or reddish-brown markings and give the seed-heads a purplish or brownish appearance.
As the flower spikelets mature they fall off as a unit, containing 2-4 brown 'seeds' (0.6-0.7 mm wide) that are held inside the bracts (i.e. glumes). The 'seeds' (i.e. nuts or achenes) are two-sided (i.e. biconvex), narrowly oval or narrowly egg-shaped in outline (i.e. narrowly-elliptic or narrowly-obovate), and about half as long as the bracts (i.e. glumes).
Reproduction and Dispersal
This species reproduces by seed and also vegetatively via creeping stems (i.e. stolons and rhizomes). Its can spread via these creeping stems (i.e. stolons and rhizomes) to cover large areas. Seeds and segments of these stems might also be dispersed by water and in dumped garden waste.
Environmental Impact
Cyperus (Cyperus teneristolon ) is on the Alert List for Environmental Weeds, a list of 28 introduced plants that threaten biodiversity and cause other environmental damage in Australia. It is regarded as a weed in Africa and South America, in agricultural areas with climatic and environmental conditions similar to those that occur in Australia. Hence it is seen as a potential threat to Australia’s environment and agricultural productivity.
The only known occurrence of this species in Australia is located in the Minnehaha Reserve in the greater Blue Mountains National Park, in New South Wales. Its presence here suggests that it has the potential to invade natural habitats and conservations areas, particularly in wetter sandy sites in highland regions.
Other Impacts
It is also a potential weed of lawns, turfed areas, gardens and horticultural crops. This species has become a significant weed of crops of the East African highlands, particularly in Kenya.
Legislation
Currently not declared or considered noxious by any state government authorities.
Similar Species
Cyperus (Cyperus teneristolon) is very similar to many other native and introduced sedges (Cyperus spp.) and other closely-related species (i.e. to many to mention). While some of these species have creeping stems (i.e. stolons and rhizomes), and many others have dense globular seed-heads, very few have purplish-brown coloured seed-heads. These three characters occurring together in cyperus (Cyperus teneristolon) generally set it apart from other similar species in Australia.