Quick Facts

Quick facts

  • Orange New Zealand Sedge (Carex testacea) is a tufted perennial herb with grass-like leaves, growing to 30–60 cm tall.
  • Its stems elongate up to as much as 3 m when fruiting.
  • It is cultivated as an ornamental because of its reddish orange foliage (best developed in full sun).
  • It has the potential to become a serious weed in gardens, pastures and native habitats.

What Does It Look Like?

What is it?

Orange New Zealand Sedge (Carex testacea) is a grass-like perennial sedge, growing to 30–60 cm tall, but elongating when fruiting, forming a smallish dense tussock. Its slender stems are triangular in cross-section, green or reddish orange, strongly drooping to prostrate when fruiting. They elongate as flowering and fruiting proceeds and may eventually reach up to 3 m in length and trail along the ground. The grass-like leaves are green or reddish orange, and about as long as the stem.

The flower head is made up of three to five cylindrical clusters of tiny flowers (spikes) close together on the inflorescence (flower structure) axis; the uppermost spike is on a slender stalk and has only male flowers, while the lower spikes are female and 0.5–2.5 cm long. The female flowers have a two-branched style.

The fruit (nut) is about 1.5 mm long, 2-faced (biconvex, that is having two convex surfaces, in cross section), egg-shaped in outline and very dark brown (Edgar 1980; Navie 2004).

The common name 'New Zealand Sedge' is used for several species of Carex introduced to Australia from New Zealand.

For further information and assistance with identification of New Zealand Sedge, contact the herbarium in your state or territory.

Flower colour

Brown

Growth form (weed type/habit)

Herb

Where it currently grows? Preferred habitat

Orange New Zealand Sedge grows in temperate regions, in more open areas such as grasslands and roadsides, and even on sand dunes in New Zealand (Edgar 1980; Parsons & Cuthbertson 2001). It is reported to be tolerant of road pollution and dry to moist or even brackish conditions (Curtis & Morris 1994).

Are there similar species?

Orange New Zealand Sedge has very elongated flowering stems like the other New Zealand species Carex flagellifera, but they differ in leaf and spikelet features (Healey & Edgar 1980; Parsons & Cuthbertson 2001). The Australian native Bergalia Tussock (C. longebrachiata) also has very long flowering stems, but it differs in being a much more robust plant and having three-branched, rather than two-branched, styles in the female spikelets. It is best to consult a herbarium to confirm identifications because of the difficulty of distinguishing the many Carex species (native and naturalised), especially in south-eastern Australia (Healy and Edgar 1980; Wilson 2008 pers. comm.).

Why Is It A Weed?

What are its impacts?

Agriculture: Orange New Zealand Sedge can invade pastures, native grasslands and woodlands and is locally significant in New Zealand. It is not yet an important weed in Australia, but it has the potential to be a serious weed in gardens, pastures and native habitats (Tasmanian Department of Primary Industries and Water 2007).

How does it spread?

Orange New Zealand Sedge is spread by seed and also by creeping underground stems (rhizomes) (Parsons & Cuthbertson 2001; Navie 2004). There is potential for Orange New Zealand Sedge to be spread through horticulture, as an escapee from gardens and landscape plantings.

What is its history in Australia?

Orange New Zealand Sedge was introduced as an ornamental plant that is popular for its usually brightly coloured leaves (this colour is best developed in full sun). It is planted in home gardens, public parks and roadside nature strips in several states (Curtis & Morris 1994; Parsons & Cuthbertson 2001).

Orange New Zealand Sedge was first recorded as naturalised in Australia in 1983 in Victoria (Hosking 1997) and was introduced in Tasmania in 1986 for planting on roadside nature strips (Curtis & Morris 1994). It has also been introduced into horticulture in New South Wales and South Australia (Curtis & Morris 1994), but there are no records of Orange New Zealand Sedge being naturalised in these states. This introduced plant could become invasive (Curtis & Morris 1994; Parsons & Cuthbertson 2001).

How To Manage It?

Best practice management

Prevention of introduction and spread and early detection are key to weed management (Tasmanian Department of Primary Industries and Water 2007).

Non-chemical control: Physical control: Physical removal is recommended where only scattered plants occur.

Chemical control: Sedges are generally susceptible to some herbicides (Parsons & Cuthbertson 2001).

Please see the Australian Pesticides and Veterinary Medicines Authority for chemical information http://www.apvma.gov.au 

Does it have a biological control agent?

NO

When does it grow? (lifecycle/growth calendar)

Flowering occurs mostly during summer. In general, sedges set seed in summer-autumn and then seed can germinate at any time although plants do not flower until at least 2 years old (Parsons & Cuthbertson 2001; Navie 2004).

Where Is It Found?

Which states and territories is it found?

TAS, VIC

What areas within states and territories is it found?

There are very few naturalised records of Orange New Zealand Sedge in Australia. It has been recorded in the Hobart area in Tasmania (Tasmanian Department of Primary Industries and Water 2007; M. Baker 2008 pers. comm.). There is a record of the species spreading from roadside plantings in Melbourne in Victoria (G. Carr in Hosking 1997). Orange New Zealand Sedge has also been introduced into horticulture in New South Wales and South Australia, but there are no records of escapes from cultivation in these states (Curtis & Morris 1994).

Where does it originate?

Orange New Zealand Sedge is native to New Zealand, where it is found scattered on both main islands, from sea level to 1000 m altitude (Edgar 1980).

National And State Weed Listings

Is it a Weed of National Significance (WONS)?

NO

Where is it a declared weed?

TAS, WA

Government weed strategies and lists – Weeds Australia

Is it on the National Alert List for Environmental Weeds?

NO

Government weed strategies and lists – Weeds Australia

Is it on the Agricultural Sleeper List?

NO

Government weed strategies and lists – Weeds Australia

Names And Taxonomy

Main scientific name

Carex testacea

Other scientific names (synonyms)?

 

Does it have other known common name(s)?

New Zealand Sedge, Orange-green Sedge, Speckled Sedge Trip-me-up (New Zealand)

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