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Pampass grass

Botanical Name Cortaderia selloana
Family Poaceae
Origin South America

Identification

Tall growing cutting grass with erect seed heads variable in shape and colour, white, pink or purple. Flowers mid March to late May (later than purple pampas and native toetoe). Leaf sheaths hairless or sparsely hairy, foliage tips at variable levels above ground. Introduced species have leaves which curl at the base of the plant when they are dead. Native toetoe is easily distinguished by the waxy surface on the leaf sheaths and also the golden flower heads.

Habitats

Key communities are coastal and lowland shrub and forest margins, sand dunes and hinterland, cliffs, bluffs, riverbeds. Also of note are inshore islands and coastal areas, disturbed forest and shrublands, sand dunes, roadsides, railway lines, farm hedges, quarries, wasteland, exotic plantations. Common in the coastal Bay of Plenty.

Impact to Biota and Ecosystems

Invades disturbed areas and open rocky sites. Competes with and smothers other vegetation. Spreads quickly. Creates a fire hazard with excessive build up of dry material (dry leaves, leaf bases and flowering stalks).

Dispersal Routes, Vectors, Infestation Sources

Large amounts of seed produced per plant. Seed dispersed by gravity, wind, humans and other vertebrate animals, pampas has no set routes of dispersal. Harvesting in exotic plantations creates opportunity for seed germination. The area then is usually left undisturbed in which time large pampas colonies develop. Grazing of stock on coastal dunes in forest management encourages pampas growth to displace palatable native toetoe.

Management

Management 

Physical Control Small plants can be grubbed out. Control large areas of infestation (e.g. in pine plantations and wastelands) by grazing cattle in the area (not on coastal dunes - see warning above). Dig out large plants with a digger.
Disposal

Compost or mulch.

Chemical Control

Can be sprayed using Gallant or Glyphosate + Penetrant. Complete coverage is required to achieve good results. Alternatively graze, cut or burn foliage and spray regrowth. Control exacerbates fire hazard.

(i) Glyphosate + Penetrant

Rate - 1 litre Glyphosate + 200 ml Penetrant/ 100 litres water.

(ii) Gallant

(Controls grasses and some sedges; ineffective on broadleaf spp.)

Rate - Handgun 500 ml Gallant + 500 ml Uptake oil or crop oil/100 litres water. Knapsack 150 ml Gallant + 50 ml crop oil/10 litres water.

Biological Control

 
Recommended Approach

Grub out small plants. For larger infestations spray with Gallant or Glyphosate.

Further Comment

Pampas should be distinguished from native toetoe to protect native species from destruction.

This plant is prohibited from propagation, sale and distribution within New Zealand!