Cortaderia jubata
NPPA pest plant
Environmental Weed (2024)
Common names
purple pampas grass
Biostatus
Exotic
Category
Vascular
Structural class
Grasses
Flower colours
Violet/Purple
Detailed description
Large-clump-forming grass to 3 m+. Leaf base very hairy, no white waxy surface. Leaves with conspicuous midrib which does not continue into leaf base, no secondary veins between midrib and leaf edge; both leaf surfaces dark green, snap readily when tugged; dead leaf bases spiral like wood shavings. Flowerhead erect, dense, uniform, fluffy, bright purple, fading to dirty brown.
Similar taxa
Can be separated from native toetoe (Austroderia spp.) by the prominent single midrib on the leaves (native cortaderia have several prominent veins, making their leaves difficult to tear across). Can be separated from C. selloana by the hairy leaf bases, and the white (to pale pink) flowering spike extends further from the clump.
Habitat
Terrestrial. Forest light gaps, slips, margins, disturbed sites, open habitats, riverbeds, cliffs, inshore and offshore islands, tussockland, fernland, herbfield, duneland, coastline, gumlands, salt marsh, estuaries, shrublands.
Conservation status
Not applicable
Detailed taxonomy
Family
Poaceae
Ecology
Flowering
January, February, March
Fruiting
March–April (Timmins & MacKenzie 1995).
Year naturalised
1965
Origin
South America
Reason for introduction
Cortaderia jubata
Tolerances
Adult plants are tolerant of drought and frost, prefers high light. Seedlings are intolerant to drought and slightly tolerant of frost, slightly intolerant to intolerant of poor drainage.
Life cycle and dispersal
Perennial. Seed germination occurs in autumn. The plants breeding system is autonomous apomixis and the flower type is apomictic. All plants are female and all flowers are capable of producing seed without pollination. Reproduction primarily by seed but clumps can get quite large. All plants are female but viable seed is produced by apomixis. Seed production is high, averaging one million per inflorescence in first year of flowering. It is unlikely that this plant forms a long term seed bank.
Seed is dispersed by gravity, man, vertebrates, machinery, in gravel and by wind. The seed is very light and is wind dispersed up to 50km.
Other information
National Pest Plant Accord species
This plant is listed in the 2020 National Pest Plant Accord. The National Pest Plant Accord (NPPA) is an agreement to prevent the sale and/or distribution of specified pest plants where either formal or casual horticultural trade is the most significant way of spreading the plant in New Zealand. For up to date information and an electronic copy of the 2020 Pest Plant Accord manual (including plant information and images) visit the MPI website.
Environmental Weed (2024)
This plant is named in a list of 386 environmental weeds in New Zealand 2024 prepared by DOC. 759 candidate species were considered for inclusion on this new comprehensive list of environmental weeds in New Zealand. The species considered were drawn from published lists of weed species, lists of plants that must be reported or managed by law if observed, existing national and regional programmes and agreements for pest management, and species already managed by the Department of Conservation (DOC). Candidate species were then assessed to see if they were fully naturalised and whether they have more than minor impacts in natural ecosystems. Read the full report here.
NVS code
The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.
CORJUB
Referencing and citations
References and further reading
Timmins SM, Mackenzie IW. 1995. Weeds in New Zealand Protected Natural Areas database. Department of Conservation Technical Series 8. Department of Conservation, Wellington, NZ. 282 p.