Pampas grass

Other Common Names: Cortaderia, Silvergrass, Cut Throat grass, Uruguayan pampas grass, White pampas grass 

Typically reaches maturity within 2 to 3 years, grows to a height of 3 to 4 metres, and has a relatively short-lived seedbank, with seeds remaining viable in the soil for up to 2 years.

• Seeds produced on female or bisexual plants.
• Seeds formed by self-fertilisation or apomixis.

• Roots can be up to 3.5 m deep.
• Plants have rhizomes forming a crown.
• Rhizomes capable of resprouting if damaged or detached.

Often found in sunny locations, this species can establish across a wide range of soil types. Seedlings are sensitive to frost but become more tolerant as they mature. It is tolerant of drought, salinity, and waterlogging. Seeds can germinate under diverse conditions, with optimal establishment in sandy soils with available moisture and partial shade rather than full light. It prefers wetlands and swamps but also occurs in disturbed areas, open bushland and woodlands. Seedling recruitment and survival are enhanced by soil disturbance.

Similar native species: Similar to Gahina species (saw-sedges) but can be distinguished as this species has more open branched seed heads and shiny red or black seeds. Similar to Cortaderia selloana subsp. jubata (Pink pampas grass) but can be distinguished by its pinkish purplish colour flowers and dark green leaves compared to the C.selloana’s whitish silvery colour flowers and greyish green coloured leaves. 

Similar non-native species: Similar to Arundo donax (giant reed) but can be distinguished as the leaves of the C.selloana arise from the basal tuft rather than being spaced evenly along the stems like the giant reed.

Seeds are primarily dispersed by wind and can travel long distances due to the long, fine hairs on the lemma. They are also spread through slashing activities, water movement, garden refuse and by attaching to animal fur.

• Outcompetes native vegetation.
• Produces large amounts of biomass creating significant fire hazards.
• Restricts regeneration of native trees and displaces native plant species.
• Rapid growth, large biomass and high seed production enable spread.
• Dense stands restrict access for native fauna, people and livestock (impenetrable thickets if left unmanaged.

Introduced to Australia in 1800s. Widely established in ornamental gardens and used as a wind break and fodder plant in agriculture.