What does it look like?
Nassella tussock is a perennial tussock-forming grass with fine-bladed, tightly rolled, light green or yellowish-green leaves. Plants are erect when young but start drooping with age, growing up to 70cm tall and 80cm wide. The leaf blades are extremely tough and wiry, and do not break when pulled. You will notice a rough texture when running your fingers down the leaves. It flowers in October and has a purplish tinge, producing small purple seeds carried on slender drooping stalks. Roots are deep, matted and fibrous with a swollen stem just above the ground.
Nassella tussock establishes in open sites in pasture, disturbed shrubland, tall and short tussockland, bare land, river systems, and rocky and coastal areas. In New Zealand it occurs most frequently in drought-prone grasslands, particularly in South Canterbury and Otago.
Why is it a problem?
Nassella tussock is tolerant to drought, fire, and grazing but does not tolerate shade, salinity or waterlogging. It can invade native ecosystems such as tussock grassland and suppresses the growth of low-growing species. It’s generally unpalatable and indigestible to stock so reduces available grazing area.
Nassella tussock reproduces by seed that disperses by wind, with each mature plant capable of producing more than 100,000 seeds per year.
Control methods
If you think you have found Nassella tussock on your property, please report it to us on 06 835 9200.One of our biosecurity advisors will carry out the necessary control.
More information
Nassella tussock is listed as a Progressive Containment pest in the Hawke’s Bay Regional Council Regional Pest Management Plan 2018-2038.
Related links
- https://agpest.co.nz/pest-directory/#weeds
- http://apps.mpi.govt.nz/applications/nzpests-view/Article/626/Nassella
- https://www.nzpcn.org.nz/flora/species/nassella-trichotoma/
- https://www.nzflora.info/factsheet/Taxon/Nassella-trichotoma.html
- https://www1.maf.govt.nz/uor-cgi/uor.pl/show?species_id=39627
- https://www.hbrc.govt.nz/assets/Document-Library/Plans/Regional-Pest-Management-Strategy/Hawkes-Bay-Regional-Pest-Management-Plan-2018-2038.pdf
- NPPA and the control of weeds | NZ Government
Notify Council
If you think you've found this pest, please get in touch with our Biosecurity Team at biosecurity@hbrc.govt.nz or call us on 0800 108 838.
Management Programme
National Pest Plant Accord
All plants on MPI's National Pest Plant Accord (NPPA) are unwanted organisms under the Biosecurity Act 1993 whose formal or casual trade contributes significantly to their spread.
Plants on the Accord cannot legally be propagated, distributed, or sold in New Zealand. If allowed to spread further, these pest plants could seriously damage our economy and environment.
Progressive Containment Programme
There are a number of pests that are well established in the Hawke’s Bay region but their present infestation levels are still low enough for those levels to be reduced region-wide through a progressive containment programme. Progressive Containment programmes have the less specific aim of reducing levels of infestation within their respective management zones. While the general intent is to reduce these infestations to zero-levels at some time into the future, the primary focus of a progressive containment programme is to preventing a pest from spreading. For well-established pests whose harmful effects and spread can still be reduced, progressive containment offers the best ratio of cost to benefits.
The goal is to maintain a pest population at the lowest feasible level and confine it to a particular area while reducing numbers over time. In some cases this will result in fewer sites infested or in others the overall density of the pest will reduce over a 10 year duration period. Containment programmes usually target habitats of high ecological value that require protection and restoration.
Unwanted Organism
An unwanted organism is any organism that's capable of causing harm to natural or physical resources (like forests and waterways) or human health. A number of introduced pests in New Zealand are classed as unwanted.
More informationRules
Plan Rule 5
Except where an occupier of land has entered into a Written Management Agreement approved by Hawke's Bay Regional Council, an occupier of land shall;
a) destroy all apple of Sodom, Australian sedge, cotton thistle, Darwin's barberry, nassella tussock, saffron thistle, velvetleaf, and woolly nightshade plants on their land
b) destroy all Japanise honeysuckle plants on their land within the defined containment area
c) destroy all old man's beard plants on their land within the Kaweka and Ruahine Ranges buffer area and containment area.
Taxonomies
FamilyPoaceae
TypePlants
GroupGrass
HabitatLand
Management ProgrammeNational Pest Plant AccordProgressive Containment ProgrammeUnwanted Organism
RulesPlan Rule 5
