GIANT PARRAMATTA GRASS

Giant Parramatta grass (Sporobolus fertilis) is a tall, aggressive perennial grass. Common in coastal areas of NSW and Qld. Giant Parramatta grass can dramatically decrease economic viability of grazing land and lower land values. It invades pastures and replaces more productive types of grass, especially after overgrazing or soil disturbance.

 It is a particularly serious problem in pastures in the wetter areas on the north coast of New South Wales. It is of low palatability and reduces the productivity of agricultural land by completely displacing desirable pasture species. The productivity and carrying capacity of invaded pastures can be significantly reduced, and farmers have reported losses in carrying capacity ranging from 10–80% depending on the density of the infestation. Cattle grazing in pastures infested with Giant Parramatta Grass also take significantly longer to reach equivalent weights to those grazing in uninfested pastures and the tough, fibrous nature of the stems can also increase teeth wear in livestock (Walton 2001; Navie & Adkins 2007).
The economic costs incurred in managing this species are also quite high and heavily infested areas have reduced land values. Giant Parramatta Grass can have other less obvious impacts, such as causing damage to asphalt on roadsides and tracks and decreasing the aesthetic appeal of infested areas. Large infestations may also affect fire intensity and/or frequency, particularly in winter and spring (Walton 2001).

Giant Parramatta Grass is widely naturalised in the eastern parts of Australia and is most common in the coastal regions of New South Wales and Queensland. It is occasionally also naturalised in the ACT, Victoria, and the inland parts of New South Wales and Queensland. It is also present on Christmas Island and the Cocos Islands, though it may be native to these offshore islands (Navie & Adkins 2007).
In New South Wales the heaviest infestations presently occur in the mid north coast region, between the Grafton and Kempsey districts. However, it is rapidly spreading north and south along the coast. Isolated infestations also occur around Dubbo, Cowra and Hay. In Queensland the largest infestations are found in the Mackay and Proserpine districts, in coastal central Queensland (Walton 2001).

Spray FireHawk Bioherbicide Concentrate: 50 mL/L of water. Respray when regrowth occurs from roots and/or runners. May require repeated application to obtain long-term weed control.