Common Grass Seeds

Clare Edwards, Senior Lands Services Officer – Pastures based in Mudgee

As I drive around the Central Tablelands at the moment there are many annual grasses flowering and setting seed. Some of them are predominately on the roadsides and disturbed areas but many of them are also found in pastures. Unfortunately, some of these seeds can cause significant impacts on livestock enterprises. There is a great deal of discussion and industry work being done on the damage of seed contamination. Damage includes effects on animals, the farm enterprise, the processors and whole the supply chain.

Impacts can include seeds penetrating the eyes, eyes, face and mouth, reduced intake and discomfort. Weight gain can be impacted with research indicating as few as 25 seeds per animal reducing daily weight gain up to 50%. There are issues with wool production and value with high vegetable matter. Bacterial infections, fly-strike, tetanus and blindness have also been recorded. With seeds penetrating into the skin and into the carcase this has impacts during meat and skin processing. Trimming, carcass downgrading and condemnation can all lead to loss of product weight, reduced market options and lower prices received.

At the moment the cool-season introduced annual grasses such as Barley grass, Greater Brome/Rip-gut Brome and Vulpia are predominant. The native cool-season yearlong green Spear grasses are just coming out in flower and introduced cool-season perennial Chilean needlegrass will shortly be in seed. Wiregrass, another native perennial is a little while from seeding as it is a warm season species. Click here for photos of these species. There are certainly other non-grass species that also cause damage such as Storksbill (Erodium species).

What are the Management options?

For the cool season annuals there are several options for next year, including pasture management, winter cleaning and grazing. Chilean needlegrass is Noxious Weed and information on its management and control should be sort from your Weeds County Council or Authority. Wiregrass and Speargrass are native species and any changes in botanical composition need to consider the Native Vegetation Act 2003.

Any farm planning needs to reflect stock management - time of lambing, shearing, genetic and the use of feed lotting. Likewise, understanding target markets and turn-off time are also important. Other strategies could include having a few clean paddocks to get lambs to turn-off point. The strategy table below is from the MLA publication Tips and Tools "Winning against seeds".

Table 1: Short term and long term strategies for grass seed management. (Source: MLA Tips & Tools, "Winning against seeds")

StrategyShort TermLong Term
Winter cleaningyesyes
Spray topping and spray grazingsometimesyes
Feeder lambssometimesyes
Crop rotationnoyes
Pasture improvementnoyes
Target marketnoyes
Flock structure / lambing timenoyes
Fodder conservationyessometimes
Confinement / forage cropsyessometimes
Shearing lambs and weanersyesno
Harrowing and slashingyesno


Pasture improvement may be associated with an increase in the incidence of certain livestock health disorders (eg bloat). Livestock and production losses from some disorders are possible. Management may need to be modified to minimise risk. Consult your veterinarian or adviser when planning pasture improvement.

The Native Vegetation Act 2003 restricts some pasture improvement practices where existing pasture contains native species. Inquire through your office of the Office of Environment and Heritage or your Local Land Services for further details.


The information contained in this publication is based on knowledge and understanding at the time of writing (September 2015). However, because of advances in knowledge, users are reminded of the need to ensure that the information upon which they rely is up to date and check currency of information with the appropriate officer of Central Tablelands Local Land Services or the user's independent adviser.

The product trade names in this publication are supplied on the understanding that no preference between equivalent products are intended and that the inclusion of a product name does imply endorsement by the LLS over any equivalent product from another manufacturer.

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