Top

Scientific Name
Synonyms
Family
Common Names
Origin
Naturalised Distribution
Habitat
Habit
Distinguishing Features
Stems and Leaves
Flowers and Fruit
Reproduction and Dispersal
Environmental Impact
Legislation
Management
Similar Species
Print Fact Sheet
ABCDEFGHIJKLMNOPQRSTUVWYXZ

Click on images to enlarge

infestation (Photo: Sheldon Navie)

infestation (Photo: Sheldon Navie)

habit in flower in summer (Photo: Sheldon Navie)

habit in autumn (Photo: Sheldon Navie)

leaves (Photo: Sheldon Navie)

young seed-head (Photo: Sheldon Navie)

close-up of flower spikelets (Photo: Sheldon Navie)

immature seed-head with seeds (Photo: Sheldon Navie)

mature seed-heads with seeds (Photo: Rob and Fiona Richardson)

close-up of purplish-coloured bracts and young seeds (Photo: Sheldon Navie)

close-up of mature seed sowing collar-like corona (Photo: Rob and Fiona Richardson)

close-up of 'stem seeds' in the leaf sheath (Photo: Sheldon Navie)

Nassella neesiana

Scientific Name

Nassella neesiana (Trin. & Rupr.) Barkworth

Synonyms

Stipa neesiana Trin. & Rupr.

Family

Gramineae (South Australia)
Poaceae (Queensland, New South Wales, the ACT, Victoria, Tasmania, Western Australia and the Northern Territory)

Common Names

Chilean needle grass, Chilean needlegrass, Chilean speargrass, spear grass, Uruguayan tussockgrass

Origin

Native to South America (i.e. Bolivia, Ecuador, Peru, southern Brazil, Argentina, Paraguay, Uruguay and Chile).

Naturalised Distribution

Widely naturalised in south eastern Australia (i.e. in eastern and southern New South Wales, in the ACT, in many parts of Victoria, in Tasmania and in south-eastern South Australia). Also recently recorded from a few locations in sub-coastal south-eastern Queensland.

Also naturalised overseas in Europe (i.e. in the UK and southern France) and New Zealand.

Habitat

A weed of pastures, grasslands, open woodlands, parks, roadsides, disturbed sites, waste areas and creekbanks in temperate, semi-arid and sometimes also drier sub-tropical regions.

Habit

A tussock-forming, long-lived (i.e. perennial), grass with upright (i.e. erect) or arching flowering stems (i.e. culms) usually growing 30-120 cm tall.

Distinguishing Features

Stems and Leaves

The stems have 3-4 swollen joints (i.e. nodes) that are sometimes covered in small soft hairs (i.e. they are downy).

The leaves consist of a leaf sheath, which encloses the stem, and a spreading leaf blade. The leaf blades (10-30 cm long and 1-5.5 mm wide) are either flat or somewhat rolled (i.e. involute or convolute) and either hairless (i.e. glabrous) or sparsely hairy (i.e. puberulent). Where the leaf sheath meets the leaf blade there is a small membranous flap (i.e. eciliate ligule) 0.5-4 mm long, which has tufts of hairs at either side.

Flowers and Fruit

The seed-head (5-40 cm long) is a loose, upright (i.e. erect) or nodding panicle. The numerous flower spikelets are borne singly and each contains a single floret and two purplish-coloured bracts (i.e. glumes). When mature this floret separates from the bracts (i.e. glumes) which remain on the seed-head (i.e. inflorescence) for some time afterwards. The flower spikelets (10-22 mm long) are elongated (i.e. lanceolate) and cylindrical (i.e. terete) in shape and are topped with a very long awn. Flowering occurs from late spring through to autumn, but is most common during the summer months.

Two types of seeds are produced by this species. Normal seeds are produced on the main seed-head (i.e. inflorescence). These seeds (6-10 mm long) have a sharpened, hairy tip (i.e. pilose callus) at one end and a twisted and bent awn (45-80 mm long) at the other end. Where the awn attaches to the seed there is a small membranous, crown-like structure (i.e. corona) about 1 mm long that is surmounted with tiny hairs (i.e. a coma). The other type of seed produced is called a 'stem seed' (i.e. cleistogene). These much smaller seeds are produced at the joints (i.e. nodes) of the flowering stems (i.e. culms) and are concealed in the leaf sheaths.

Reproduction and Dispersal

This species reproduces via two types of seeds. Aerial seeds are produced in its seed-heads and 'stem seeds' (i.e. cleistogenes) are produced in its leaf forks.

The aerial seeds readily become attached to animals, clothing and vehicles. Both types of seeds may also be dispersed in contaminated agricultural produce (e.g. fodder) and soil.

Environmental Impact

Chilean needlegrass (Nassella neesiana) is one of the Weeds of National Significance (WoNS) in Australia, and is regarded as an environmental weed in Victoria, south-eastern New South Wales, the ACT, Tasmania and South Australia.

Legislation

This species is declared under legislation in the following states and territories:

Management

For information on the management of this species see the following resources:

Similar Species

Chilean needlegrass (Nassella neesiana) is very similar similar to lobed needlegrass (Nassella charruana), cane needlegrass (Nassella hyalina), Texas needlegrass (Nassella leucotricha) and short-spined needlegrass (Nassella megapotamia). These species can be distinguished by the following differences:

Several other introduced grasses are relatively similar. These include serrated tussock (Nassella trichotoma), Mexican feathergrass (Nassella tenuissima), broad kernel espartillo (Amelichloa caudata), narrow kernel espartillo (Achnatherum brachychaeta), plumerillo (Jarava plumosa) and Uruguayan ricegrass (Piptochaetium montevidense). None of these species have collars (i.e. coronas) on their seeds.

In addition, several native tussock-forming grasses can look similar (e.g. Poa spp. and Austrostipa spp.). However, these species either lack ligules on their leaves, or have ligules that are fringed with hairs, and they also do not have collars (i.e. coronas) on their seeds.

Note: This page only covers those grasses that are commonly confused with this species. For a more in-depth key to all of the grasses present in Australia, see the AusGrass: Grasses of Australia CD-ROM or Flora of Australia, Volumes 43 and 44.