Management Information
Peterson (1988) cites that there is good opportunity for recovery of native plant populations if Cortaderia jubata is controlled with a strict management program.
Preventative measures: A Risk assessment of Cortaderia jubata for Australia was prepared by Pacific Island Ecosystems at Risk (PIER) using the Australian risk assessment system (Pheloung, 1995). The result is a score of 22 and a recommendation of: reject the plant for import (Australia) or species likely to be a pest (Pacific).
Physical: Physical removal of the plants is effective if they are small enough, but this method can be quite labour intensive. Good success has been obtained by physically removing the plants whereby a rope or chain is tied around plants and they are pulled out of the ground with a vehicle. Although effective, this is labor intensive. Fire has also been suggested as a method to eliminate foliage for the later mechanical removal or chemical treatment of the plant. According to George Gray (1992), Associate Resource Ecologist for the California Department of Parks and Recreation, fire will not kill pampas grass, but makes it unhappy. Madison (1994), however, found that the high silica content in the leaves of pampas grass acted as a fire retardant and fire was not very effective in eliminating the foliage.
Chemical: A number of chemical treatments are also effective and may be more practical for severe infestations. Monitoring is definitely needed to document population trends in and adjacent to preserves. The effects of the weed on native plants should be monitored as well as the effectiveness of management efforts to eradicate it. If populations are found to be increasing rapidly, an intensive effort to control its spread is necessary. If an eradication program using an herbicide (Roundup) is initiated, treatments should be followed by evaluations of effectiveness. The emphasis of most programs has been to eliminate the largest plants first to reduce the potential for seed dispersal.
Biological: In New Zealand pine plantations Cortaderia is controlled by cattle grazing (Wilcox, 2003).  
Location Specific Management InformationAustralia
It is illegal to import or grow i>C. jubata in Australia (OCA, Undated). California
Several control methods have been used in California since 1985 in the control of Cortaderia jubata; herbicidal control efforts and monitoring of in the Nature Conservancy's Ring Mountain Preserve, Tiburon, California (Peterson 1988), mechanical control efforts using ropes/chains and vehicles to uproot tussocks in the Camp Pendleton Marine Corps Base, California (Peterson 1988), manual and herbicidal control efforts of between the Gualala River and Point Arena areas by the Dorothy King Young (DKY) Chapter of the California Native Plant Society (Madison 1993; 1994), mechanical removal of C. jubata using heavy equipment in the Golden Gate National Recreation Area (Nelson 1991) and manual control efforts in the California state parks of the Santa Cruz mountains by the Wildlands Restoration Program (Moore 1994) cited in the HNIS Report for Cortaderia jubata; A product of the Hawaiian Ecosystems at Risk Project accessed from http://www.hear.org/hnis/reports/HNIS-CorJub.pdf. Hawaii
Cortaderia jubata is legally declared as a noxious weed in the state of Hawaii and sale or transport is illegal (DOFAW, Undated).
From 1992 mechanical and herbicidal control efforts have been going on in upcountry Maui and Haleakala National Park by National Park Service resource management personnel, Biological Resources Division-USGS personnel and Sierra Club volunteers cited in the HNIS Report for Cortaderia jubata; A product of the Hawaiian Ecosystems at Risk Project accessed from http://www.hear.org/hnis/reports/HNIS-CorJub.pdf. Nelson
C. jubata has been designated as a 'Progressive control pest' by the the Tasman-Nelson Regional Pest Management Strategy. The strategy has its effect over the combined area that lies within the administrative boundaries of the Tasman District Council and Nelson City Council. The objective of the strategy is to reduce the distribution and density of C. jubata in the Tasman-Nelson region during the term of the Strategy. Please see Hierarchy of Plant Designations for an explanation of designation terminology. New Zealand
Cattle grazing is used as a means of control of C. jubata in forests (Wilcox, 2003).
Mechanical and chemical control recommendations have been made for C. jubata invading forest plantations of New Zealand (Anonymous 1985).Another approach adopted is replacing pampas grass with native species (Anonymous 1987) cited in the HNIS Report for Cortaderia jubata; A product of the Hawaiian Ecosystems at Risk Project accessed from http://www.hear.org/hnis/reports/HNIS-CorJub.pdf.. Poor Knights Islands
Control of Cortaderia spp. began in 1991, focussing on three obvious infestations on the coastline. It involved one trip per year by volunteers. In 1996, a Weed Eradication Strategy was developed. The islands were split into three management zones: weed sites, weed free sites prone to invasion, and weed free sites not prone to invasion. Existing weed sites occurred in areas of disturbance associated with exposed coastal faces, shrubland and broadleaf forest. An aerial search was conducted in early summer, and sweep searches were conducted over the weed sites during spring, when flowering is commencing. Any plants found were removed from the island. There has been a dramatic decline in numbers. A four year seedling absence will be required before sites can be declared weed-free. Reinvasion remains a threat, both by wind dispersal, and by the spread of seeds by management staff.
Both species of Cortaderia have been removed from the Poor Knights but eradication has never been achieved. A zero density adult population is being sustained . All plants were thought to have been removed in 2001/02 but further plants have since been found, some of which had set seed. Reinvasion from the mainland is suspected to be occurring. Sporadically over the last 4years individual plants have continued to appear in areas of the islands where there have not been adult pampas grass recorded. Plants have also occurred in old weed sites as recently as last year - potentially either old seed in the soil or seed rain shadow as well (Glen Coulston., pers.comm., February 2006). Rangitoto Is. (North Island)
In 1995, a weed control programme was initiated on Rangitoto Island, with 72 weed species identified. These were split into three priority classes, each with a management objective. The long term aim for this species is sustained control. Taranaki Region (North Island)
C. selloana is classified as a 'Containment pest plant' in the The Pest Management Strategy for Taranaki. 'Containment pest plants' are pest plants that are abundant in suitable habitats in a region or part of a region and for which the long-term goal is to prevent the spread of the plant to new areas or to neighbouring properties.
Each pest plant has a management programme according to its designation. These programmes are summarised in the series of bulletins 'Pest Plant Facts'. Please see Common pampas: C. selloana for pest plant facts and management programmes. Tasman District
C. jubata has been designated as a 'Progressive control pest' by the the Tasman-Nelson Regional Pest Management Strategy. The strategy has its effect over the combined area that lies within the administrative boundaries of the Tasman District Council and Nelson City Council. The objective of the strategy is to reduce the distribution and density of C. jubata in the Tasman-Nelson region during the term of the Strategy. Please see Hierarchy of Plant Designations for an explanation of designation terminology. Tasmania
Efforts are ongoing in the mechanical and herbicidal control of pampas grass in natural and agricultural settings cited in the HNIS Report for Cortaderia jubata; A product of the Hawaiian Ecosystems at Risk Project accessed from http://www.hear.org/hnis/reports/HNIS-CorJub.pdf..
Management Resources/Links
2. Collins, J.N, May M, Grosso C. 2003. Pampas grass Cortaderia jubata, Cortaderia selloana. Practical Guidebook to the Control of Invasive Aquatic and Wetland Plants of the San Francisco Bay - Delta Region.
Summary: Information on description, economic importance, distribution, habitat, history, growth, and impacts and management of species.
Available from:
http://legacy.sfei.org/nis/pampasgrass.html [Accessed 22 May 2010].
The Guidebook is available from: http://legacy.sfei.org/nis/index.html 4. Environment Waikato. 2002. Pampas (Cortaderia jubata, C. selloana, including cultivars) 6. Landcare Research. Prospects for Biological Control of Pampas Grass (Cortaderia spp.) (Poaceae) Landcare Research Contract Report: LC9900/138 (2000)
Summary: Report on distribution, impacts and management in New Zealand. 7. National Pest Plant Accord, 2001. Biosecurity New Zealand.
Summary: The National Pest Plant Accord is a cooperative agreement between regional councils and government departments with biosecurity responsibilities. Under the accord, regional councils will undertake surveillance to prevent the commercial sale and/or distribution of an agreed list of pest plants.
Available from: http://www.biosecurity.govt.nz/pests-diseases/plants/accord.htm [Accessed 11 August 2005] 8. New Zealand Plant Conservation Network, 2005. Unwanted Organisms. Factsheet Cortaderia jubata 13. Taranaki Regional Council. 2003. Common pampas/Purple pampas (Cortaderia sellona / Cortaderia jubata). The Pest Plant Management Section. 14. Tasman District Council (TDC) 2001. Tasman-Nelson Regional Pest Management Strategy Results Page: 1
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