Quick Facts

Quick facts

• Originally from South America, Cane Needle Grass (Nassella hyalina) is a perennial tussock-forming grass to 0.8 m (or sometimes 1.5 m) high, with branched stems, leaves are up to 20 cm long, flat or in-rolled, with flowering heads (called panicles) grow to about 25 cm long with sharp seeds.
• Producing abundant flowering seeds, and also produces hidden stem seeds, found at the base of the plant, and in the joints (nodes) of the stem which means the plant can reproduce even when the main seed head is destroyed.
• The current distribution is limited to Victoria around the outer western suburbs of Melbourne and central Victoria and across New South Wales, but has the potential spread to all other southern states and affect 0.9 million hectares.
• It poses a threat in cool to warm temperate, preferring areas with rainfall over 500 mm, grows in fertile to poor sites from dry to damp sites like riparian grasslands.
• Invade pastures and some native vegetation forming dense infestations which exclude other more desirable species.
• Reduces nutritional value relative to improved pastures, and if animals are present in summer when the sharp flowering seeds are produced, these can injure and damage animals, downgrading produce.
• Rehabilitation of infested land is very difficult, for best results, combine herbicide application with physical removal, crop rotation, pasture sowing and  high intensity grazing management for a short duration.
• Prevention and early intervention are the most cost-effective forms of weed control.
• Its sharp seeds are easily spread by attaching to clothing, animals fur and machinery.
• All control programs should aim to reduce the amount of seed produced, with prevention and early detection the most cost-effective form of weed control, with quarantine and good hygiene within infestations preventing spread.

What Does It Look Like?

What is it?

Cane Needle Grass (Nassella hyalina) is a perennial tussock-forming grass to 0.8 m (or sometimes 1.5 m) high, with stems occasionally branched and nodes (joints on the stems where leaves or branches arise) are glabrous (smooth without hairs). The leaves are up to 20 cm long and 4 mm wide, flat or in-rolled, strongly ribbed and with scabrous (rough to touch) margins. Leaves have a leaf-sheath rolled around the stem where the blade meets the stem. The ligule a small membranous flap, 0.2–2 mm long, in-rolled hairless is at the junction of the leaf blade and the leaf sheath meet on the stem. The ligule can be located by tracing a leaf down to where it joins the sheath and bending the leaf back at this point. Cleistogenes, sometimes referred to as stem seeds, (modified spikelet produced within the lower leaf-sheaths) have been observed, and enable the plant to produce seed even if the main seed head is destroyed.

The branching flower heads (called panicles) grow to about 25 cm long. Many spikelets (flowers) are contained within flower head. Glumes (pointed bracts) 9–12 mm long,  hyaline (translucent, usually delicately membranous and colourless) to straw-coloured, with pointed tips, the lower up to 2 mm longer than upper. Contained within the glumes is a lemma which becomes the husk of the seed.

The pointed sharp seeds are pale brown to purple with a long awn (bristle-like appendage). A distinct feature is the collar-like structure surrounding the base of the awn where the awn attaches to the seed, called a corona or crown, 0.5–1 mm long excluding the erect apical hairs or slender spines to 0.3 mm long. The lemma (seed) is  3.5–4.5 mm long (excluding corona), pale brown or purplish at maturity, partially smooth glabrous with some small like wart-like growths, and except near callus and along midrib. The callus (the point of the seed) is curved and silky hairy 0.5–1 mm long. The awn is twice bent, 35–40 mm long, 4–8 mm to the first bend, and rough to the touch (Jacobs & Everett 1993); Walsh (1994); Wheeler et al. (2002); CRC (2003); Sainty & Associates (2004), Richardson et al. (2006); VicFlora 2016).  For further information and assistance with identification of Cane Needle Grass contact the herbarium in your state or territory.

Flower colour

Green

Growth form (weed type/habit)

Grass

Where it currently grows? Preferred habitat

Cane Needle Grass is found in a variety of habitats, usually on fertile soils, including black volcanic soils and grey cracking clays on basalt near Melbourne (CRC 2003), and requires 500 mm of annual rainfall or more (Humphries & Florentine 2021).

Like many other Stipoid grasses, Nassella species often invade sites that are already highly degraded, especially land with higher fertility soil that has been used for grazing or farming (CRC 2003). In addition to growing in pastures and weedy areas on grassland plains, Cane Needle Grass has invaded open woodlands and native grasslands. It has also been observed growing in areas subject to seasonal waterlogging and in riparian vegetation (McLaren et al. 1998).

Are there similar species?

Cane Needle Grass is hard to identify because of its similarity to native spear grasses (Austrostipa species) and other Nassella species. They all have sharp seeds with a long curved or bent awn and hairy tip. However, Nassella species have strongly overlapping margins of the 'lemma' (the seed coat), which make it difficult to open the mature seeds. Also, the seeds of most Nassella species (except Serrated Tussock) possess a corona, a raised crown at the joining of the seed body and the tail (the awn). The corona is absent in Austrostipa species (CRC 2003). Introduced Nassella species have a membranous ligule (a small flap at the junction of the leaf blade and leaf sheath) whereas native species either have no ligule or the ligule is fringed with hairs (Muyt 2001; McLaren et al. 1998; Navie 2004; Best 2008).

Differences between Cane Needle Grass and similar looking species are illustrated by CRC (2003) and Richardson et al. (2006). Plant identification keys for the species of Nassella occurring in New South Wales are provided by Jacobs & Everett (1993) and Wheeler et al. (2002); VicFlora 2016.

Queensland Goverenemt (2016) states that the species can be distinguished by the following differences:

Cane needle grass (Nassella hyalina) has seeds with relatively short awns (20–45 mm long) and a short corona (less than 1.5 mm long). Its flower spikelets are relatively small (5–12 mm long) and it produces stem seeds (i.e. cleistogenes).

Lobed needle grass (Nassella charruana) has seeds with relatively long awns (more than 45 mm long) and a long corona (5–6 mm long). Its flower spikelets are relatively large (16–20 mm long) and it does not produce stem seeds (i.e. cleistogenes).

Chilean needle grass (Nassella neesiana) has seeds with relatively long awns (more than 45 mm long) and a short corona (less than 1.5 mm long). Its flower spikelets are relatively large (10–22 mm long) and it produces stem seeds (i.e. cleistogenes).

Texas needle grass (Nassella leucotricha) has seeds with relatively long awns (more than 45 mm long) and a moderately-sized corona (1.5–2.5 mm long). Its flower spikelets are relatively large (10–17 mm long) and it produces stem seeds (i.e. cleistogenes).

Short-spined needle grass (Nassella megapotamia) has seeds with relatively long awns (more than 45 mm long) and a short corona (less than 1.5 mm long). Its flower spikelets are relatively small (7–10 mm long) and it does not produce stem seeds (i.e. cleistogenes).

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.

Why Is It A Weed?

What are its impacts?

Cane Needle Grass is on the Alert List for Environmental Weeds, a list of 28 non-native plants that threaten biodiversity and cause other environmental damage. Although only in the early stages of establishment, these weeds have the potential to seriously degrade Australia's ecosystems (CRC 2003). 

Agriculture: Although not currently seen as a threat to agriculture, Cane Needle Grass could have a serious impact on agricultural production in the future. It is drought tolerant and forms dense, competitive infestations. It is closely related to Serrated Tussock, a Weed of National Significance, which costs south-eastern Australia's grazing industries more than $40 million annually in control and lost production. Several species of Nassella have proved difficult to control and are now environmental and agricultural weeds (CRC 2003). Besides loss of production and environmental damage, the sharp seeds of Nassella species can damage sheep skins and carcasses and contaminate fleeces (CRC 2003). While some reports describe it as palatable to stock and suitable as reasonable fodder, Cane Needle Grass is also described as quite sparse with only intermediate feed value (CRC 2003).

Native ecosystems: Cane Needle Grass threatens a number of conservation reserves west of Melbourne. It appears to be spreading, especially in wetter areas within open native grasslands. It has the potential to affect the biodiversity of riverbank vegetation and grassland, especially in areas that remain wet for long periods (CRC 2003).

How does it spread?

Cane Needle Grass spreads by seeds. Although the exact amount of seed produced is not known, both of the closely related species, Serrated Tussock (Nassella trichotoma) and Chilean Needle Grass (N. neesiana), can produce tens of thousands of seeds per plant per year (CRC 2003).

The seeds are very sharp, and readily attach themselves to clothing, fur and equipment. Seeds can also be spread when soil is moved. Most seeds are produced in flower heads at the ends of stems; however, Cane Needle Grass has an unusual feature in that it also produces 'stem' seeds, which are formed at the base of the clump. These hidden seeds enable the plant to reproduce despite grazing, slashing and fire (CRC 2003).

Cane Needle Grass also has an unusual seed dispersal mechanism. After seed drop, the second last stem node (joint) becomes fragile and can be broken by passing animals, wind and water. This disperses the hidden seeds that are contained in the above-ground sections of the stems (CRC 2003).

What is its history in Australia?

It is not known exactly how Cane Needle Grass was first introduced into Australia. Seed samples were imported in 1930, 1945, 1957 and 1959 as a potential pasture and soil-conservation species, as part of the Commonwealth Plant Introduction program, and these were trialed at least at Trangie, New South Wales (Cook & Dias 2006). It was first collected in New South Wales in 1951 from between Glen Innes and Inverell in the Northern Tablelands-North Western Slopes region. In Victoria it was first collected in 1964 from Woodstock, between Yan Yean and Donnybrook (Walsh 1994).

How To Manage It?

Best practice management

Early detection and eradication of Cane Needle Grass are important to prevent infestations of Cane Needle Grass, that currently has a limited distribution. Small infestations can be easily eradicated if they are detected early but continuing surveillance is needed to ensure no re-infestations occur (CRC 2003). Because there are few Cane Needle Grass infestations, and it can potentially be eradicated before it becomes established, any new outbreaks should be reported immediately to your state or territory weed management agency or local council. Do not try to control Cane Needle Grass without their expert assistance. Control effort that is poorly performed or not followed up can actually help spread the weed and worsen the problem (CRC 2003). No formal observations or trials investigating control methods have been conducted on Cane Needle Grass, but where it occurs in native grasslands there are some general principles that apply.

Non-chemical control: Physical control: The ideal removal method involves digging out the whole plan. Hand weeding or chipping is very effective on single plants or small patches, making sure to first cut and bag any flowering seeds or stem seeds. Plants cannot be left to dry in the paddock because any basal cleistogenes (stem seeds) may germinate if left. The whole plant needs to be destroyed. 

Mowing and slashing may reduce seed set in the flower heads but it can actively disperse stem seeds if machinery is not kept clean. Mowing with a catcher mower during flowering will reduce seed set but it will not remove the basal cleistogenes (stem seeds). Clippings must be burnt and the mower must be thoroughly cleaned before it is used elsewhere (CRC 2003). Maintaining weed-free machinery and equipment is very important in preventing further spread of Cane Needle Grass. Check machinery moving onto your property and wash down vehicles and machinery in the same area to allow easy follow-up control of any seeds that may germinate. Don't buy hay, stock feed, or crop and pasture seed from infested areas. When controlling large infestations, mowing during the peak flowering period can be effective when followed up with additional mowing, timed to remove new flowers, as the plants will re-flower within two to six weeks. Mowing will not destroy infestations but can held reduce the spread of seed.

Competition and management: Control may be achieved using cultivation. Cultivation of the soil encourages seeds to germinate and these can be controlled. Sowing a dense pasture or crop will reduce the amount of Cane Needle Grass that germinates. Rotational cropping and a mix of cultivation and herbicide application can be used to prevent seedling.

Heavy intense grazing by animals at the correct time of year when no flowering seed-heads are present can be used.  It has only intermediate feed value to stock which are likely to avoid the plant when more palatable pasture species are present.  For larger areas larger mobs and a cycle of short duration of high intensity grazing followed by long rest periods offers the benefit of better pasture, fewer weeds and better livestock returns (CRC 2003). In addition, the sharp mature seeds attach to animals coats and can penetrate lips, skin and flesh causing harm to animals, downgrading and reducing the values of produce, be it wool or meat.

Mulching: Suitable for small infestations in native or urban areas, or larger infections in agricultural situations. Mulching is the the application of material over the ground such as straw, wood chips, carpet or plastic sheeting will prevent the growth of all plants, including weeds and beneficial plants. Organic mulch should be 100 mm thick, regularly topped-up as this reduces over time and used with other control methods to remove any unwanted plants that germinate.

Fire: The use of fire has a management tool has been used to burn-off and kill flowering and stem seeds in large infestations. Fire can be effective in areas with natives grassed and other Nassella species. A fire timed to encourage native grass growth can be used for competitive exclusion and targeted spot spraying (Muyt 2001). Other follow up controls methods are required to prevent regrowth and germination of seed

Chemical control: Herbicide use can be successful if effective competition from native grass species has been established to overcome the large seedbank of Nassella species (CRC 2003). Spot spraying is effective when used on individual plants and small infestations, and is used as a follow-up for other management practices to control any possible cleistogenes (stem seeds) (Muyt 2001). For up-to-date information on which herbicides are registered to control Cane Needle Grass and the best application methods and dosages, contact your state or territory weed management agency or local council. 

Also see; DPI NSW (2019);  the Australian Pesticides and Veterinary Medicines Authority for chemical information http://www.apvma.gov.au

Permits from state or territory Environment Protection Authorities may be required if herbicides are to be sprayed on riverbanks.

Does it have a biological control agent?

NO

When does it grow? (lifecycle/growth calendar)

Cane Needle Grass flowers from mid-spring until early summer. Seed is formed and drops during summer. Most vegetative plant growth and seed germination occur from autumn to winter, although some germination may occur year round under suitable conditions (CRC 2003).

Where Is It Found?

Which states and territories is it found?

NSW, VIC

What areas within states and territories is it found?

Major infestations of Cane Needle Grass occur around the outer northern and western suburbs of Melbourne and in central Victoria. Cane Needle Grass is uncommon in New South Wales where it has been found in the north-eastern part of the state and also reported for the Central Western Slopes, as well as several cultivated records (AVH 2021; CRC 2003; Sainty & Associates 2004). 

Based on climatic suitability, the potential distribution of Cane Needle Grass in Australia has been estimated at 900 000 ha, with large areas of Victoria and New South Wales at risk. However, its potential to damage the natural environment is largely unknown as it has not been adequately mapped (CRC 2003). Posses a threat to other state where it is not yet present, in particular South Australia, Western Australia, and Tasmania. 

Where does it originate?

Cane Needle Grass is native to Argentina, southern Brazil and Uruguay (CRC 2003).

National And State Weed Listings

Is it a Weed of National Significance (WONS)?

NO

Where is it a declared weed?

SA

Government weed strategies and lists – Weeds Australia

Is it on the National Alert List for Environmental Weeds?

YES

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

Nassella hyalina

Other scientific names (synonyms)?

Stipa hyalina Nees