Cradle Coast Region
Pampas Grass (Cortaderia spp.)
Control Strategy
June 2014
Cortaderia jubata (pink pampas)
Report prepared by Anthea Fergusson B. Sc.
Pampas grass (Cortaderia spp.) Control Strategy for the Cradle Coast Region. 2014
Acknowledgements
I would particularly like to thank Sue Jennings, Forestry Tasmania for information regarding the
history of pampas grass in Tasmania, and the government funded control program in the 1990’s,
as well as many of the lessons learned at that time.
Thank you also to Kiowa Fenner, Invasive Species Regional Coordinator DPIPWE for overall
information on the current status of pampas grass in the Cradle Coast Region.
Thank you to all the representatives of the various land managers who provided me with
feedback on the current status of pampas grass on their patch including municipal Councils,
Forestry Tasmania and TasRail.
Finally thank you to Ali Dugand, Cradle Coast NRM for tirelessly responding to my requests for
more information.
This project has been supported by Cradle Coast NRM through funding from the Australian
Government.
Prepared by Anthea Fergusson
Natural Values Consulting
June 2014
Publication Details
This document may be reproduced in whole or in part for the purpose of study or training, subject
to the inclusion of an acknowledgment of source and it not being used for commercial purpose or
sale. Reproduction for purposes other than those given above requires the prior permission of
Cradle Coast NRM.
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Pampas grass (Cortaderia spp.) Control Strategy for the Cradle Coast Region. 2014
1.0 EXECUTIVE SUMMARY
Over time three different species of pampas grass (Cortaderia spp.) have been
introduced to Tasmania. All pampas grass species are a declared weed under the
Tasmanian Weed Management Act (1999). Under the Act the whole of Tasmania is
classified as Zone A which means that eradication is the management objective.
This pampas grass control strategy also addresses the need to capture and record the
key information gathered during the initial pampas grass control program in the 1990’s.
A lot of time, money and effort was invested by government agencies dealing with an
emerging environmental and economic threat; the campaign included the raising of
public awareness and learning best practice control methods. If this knowledge is not
recorded then there is a very real risk that the information will be lost resulting in wasted
time, money and effort re-learning the same lessons.
Pampas grass presents both an environmental and an economic threat because the
species can invade native vegetation communities and displace native species, but also
proliferates in commercial forestry operations creating access difficulties and elevated
fire risks.
The key to the eradication of pampas grass is in the name – it is a grass. Eradication of
pampas grass is entirely possible. Grass species have a short seed life, pampas grass
seeds are viable for a maximum of 2 years (Blood, 2003).
In order to achieve the objective of pampas grass eradication a regional approach is
required. Pampas grass infestations occur on land managed by a variety of land
managers ranging from private to public lands, from property managed by utility services
to mining businesses. All land managers appear to face the same hurdles; the biggest
problems are lack of resources (money and personnel) and lack of priority given to weed
control, they also do not receive enough publicity. Some effort is being put in to pampas
control on a routine basis but not as a concerted “seek and destroy” mission. Unless the
effort is elevated to priority status pampas grass will remain in the landscape, ticking
over, ready to increase the size of infestations.
For maximum benefit a Project Officer position would need to be established to drive a
regional attack and co-ordinate participating landholders. The project officer would also
need to be a gazetted Weeds Officer with the Department of Primary Industries, Parks,
Water and Environment in order to be able to pursue compliance where necessary.
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Pampas grass (Cortaderia spp.) Control Strategy for the Cradle Coast Region. 2014
Table of Contents
1.0 EXECUTIVE SUMMARY .......................................................................................... 3
2.0 VISION ......................................................................................................................... 5
3.0 GOALS ......................................................................................................................... 5
4.0 OVERVIEW ................................................................................................................. 5
5.0 THE PROBLEM - CORTADERIA SPECIES ............................................................... 7
6.0 LAND MANAGER STATUS ...................................................................................... 8
6.1 Municipal status ...................................................................................................... 8
6.2 Public Landmanagers.............................................................................................. 8
6.3 Private Landmanagers ............................................................................................ 8
7.0 STRATEGIC APPROACH .......................................................................................... 9
8.0 RECOMMENDATIONS ............................................................................................ 10
9.0 GOALS, OUTCOMES AND ACTIONS ................................................................... 11
10.0 CONTROL METHODS ........................................................................................... 12
11.0 CASE STUDY .......................................................................................................... 15
11.0 REFERENCES ......................................................................................................... 16
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Pampas grass (Cortaderia spp.) Control Strategy for the Cradle Coast Region. 2014
2.0 VISION
No pampas grass (Cortaderia jubata, C. selloana, and C. richardii) in the Cradle
Coast Region
3.0 GOALS




All land managers in the Cradle Coast Region taking responsibility for pampas
grass control and making a concerted effort towards achieving pampas grass
free status.
A coordinated approach to pampas control across all land tenures
Best practice control information and advice easily available to all land managers
A steady reduction of pampas numbers/infestations, until it is ultimately
eradicated.
4.0 OVERVIEW
As the name suggests pampas grass (Cortaderia spp.) is a true grass species and
belongs in the Poaceae family. Pampas grass is NOT native in Tasmania; however there
are now three colonized species, meaning the species is quite “at home” in our climate
and native environment. Plants will freely flower, set viable seed and expand populations
in our landscape. The three species are Cortaderia jubata (pink pampas), C. selloana
(common pampas grass) and C. richardii (New Zealand toe toe). Although variations
exist between the species (mainly in flower colour and flowering times), botanically the
species are similar and can be treated the same way.
Pampas is a declared weed under the Tasmanian Weed Management Act (1999). The
whole of Tasmania is classified as Zone A, which means that eradication is the
management objective set by the Department of Primary Industries, Parks, Water and
Environment (DPIPWE).
Pampas grass was initially introduced to Tasmania over one hundred years ago as an
ornamental garden plant, and more recently for use in farm shelter belts. The white
flowering common pampas C. selloana has separate male and female plants and both
plants need to be present before fertile seed is released. In the early pampas grass days
(pre 1980’s) there was little potential for the species to become an aggressive weed
because predominantly female C. selloana plants were introduced and new plants were
propagated vegetatively in nurseries by dividing up existing pampas tussocks. At this
point in time pampas grass shelter belts were widely promoted and the demand
outstripped supply, leading to seed being imported from New Zealand. Unfortunately this
was mixed seed containing male C. selloana plants, as well as C. jubata and C. richardii
which had not previously been grown in Tasmania.
Within ten years it was obvious that pampas grass would become an environmental
disaster and eradication programs were organized predominantly by Tasmanian
Government departments such as the Forestry Commission and the Department of
Primary Industries. These early programs kept pampas grass infestations in check, and
today Tasmania does not have the huge infestations which threaten pine plantations in
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Pampas grass (Cortaderia spp.) Control Strategy for the Cradle Coast Region. 2014
some areas of New Zealand. However due to an uncoordinated approach, complete
eradication was not achieved.
One of the largest stumbling blocks to the removal and eradication of pampas in the
early days was the argument by property owners that they had “good pampas” – shelter
belts or garden ornamentals which had been planted in the days when only sterile
female plants were available. Therefore public perception had to be altered, there is now
no such thing as a “good pampas” either environmentally or legally.
Figure 1: Map of known pampas grass sites in the Cradle Coast Region.
Source: Cradle Coast NRM
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Pampas grass (Cortaderia spp.) Control Strategy for the Cradle Coast Region. 2014
5.0 THE PROBLEM - CORTADERIA SPECIES
Why is pampas grass a declared weed: Pampas grass will invade and thrive in a number
of different Tasmanian native vegetation communities and habitats and in the process it
can out-compete and displace indigenous plant species. Pampas grass can also have a
serious impact on commercial forestry operations. It is a colonizing plant which thrives
on bare ground and in areas that have been disturbed, for example through the
harvesting of plantation timber, road works, quarrying or mining operations, or fire. Being
a grass the species is quite pyrogenic and can be a serious fire hazard. The tussocks
can provide nesting sites for European wasps (Blood, 2003).
Figure 2: Farm shelterbelt
planting of C. selloana
(common pampas grass).
Image: A. Fergusson
Figure 3: Colonising C.
reichardii (New Zealand toe
toe) on the Queen River,
Tasmania.
Image: K. Young
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Pampas grass (Cortaderia spp.) Control Strategy for the Cradle Coast Region. 2014
Habitat: Varies from private gardens to a variety of native vegetation communities
ranging from coastal scrub to wet forest. Pampas grass will spread along corridors such
as road and rail corridors as well as colonizing swamps, streams and riparian areas
generally.
Reproduction: Pampas grass starts flowering in mid-spring, with C. selloana and C.
richardii flowering in a period extending from approximately November to March on the
West Coast. This is earlier but overlaps with C. jubata which can start flowering in
January and extend until May. Therefore the flowering period across the three pampas
grass species ranges over six months and seed set follows the production of flower
spikes. Up to 100,000 seeds can be produced from each flower head (DPIPWE), and
the windblown seed can be deposited up to 25 kilometres away from the parent plant.
Although the main vector for spreading pampas seed is the wind, seed can also spread
through contaminated soil, machinery, water and dumped garden waste. As previously
mentioned pampas grass can also be propagated by splitting up plants, therefore
severed rhizomes or dumped garden waste containing root material can re-grow.
6.0 LAND MANAGER STATUS
6.1 Municipal status
Pampas grass is present in all nine municipalities within the Cradle Coast Region. As
part of this review a questionnaire was circulated to the Weeds/NRM officers at the
various Councils, with King Island NRM supplying the answers in regard to the King
Island situation. There is some variance between the priority status given to pampas
grass control between municipalities but a similar theme flowed through the responses;
Councils lack the funds and human resources to successfully tackle the problem. Most
Councils will deal with pampas grass on Council managed land, but either do not pursue
weed control on public and privately managed land or find the process of identifying and
contacting private landholders too slow for a spontaneous response.
Cradle Coast NRM has recently supported the nine municipalities by developing a
postcard identifying four declared weeds and featured Pampas as the most dominant
target species throughout the region. This was the chosen way forward due to lack of
project funds and to provide a mechanism for education and awareness.
6.2 Public land managers
Public land managers cover government departments and agencies such as Parks and
Wildlife, Forestry Tasmania and Crown Land Services. Public land managers also
include the agencies which manage road, rail and energy infrastructure. Pampas grass
is present on publicly managed land.
6.3 Private land managers
Private land managers include private individuals as well as companies managing
mining leases and timber plantations. Pampas grass is present on privately managed
land.
Cradle Coast Natural Resource Management (NRM) has assisted various land
managers with pampas grass control over a number of years, through publicity
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Pampas grass (Cortaderia spp.) Control Strategy for the Cradle Coast Region. 2014
campaigns and also by directly employing weed contractors to control and map the
location of plants.
7.0 STRATEGIC APPROACH
The key to the eradication of pampas grass is in the name – it is a grass species with a
short seed life. Blood (2003) states that seeds are viable for a maximum of 2 years.
There is no stored seed bank of viable seed in the soil for fifty plus years like gorse and
broom, and it is killed easily by common grass herbicides. When the fact that it is NOT
hard to eradicate pampas grass is grasped by those responsible for controlling this
weed, and a planned and methodical attack is made, it is possible to achieve eradication
in quite a short timeframe. The most difficult issue is locating the entire seed source
(plants). C. jubata is considered the most common pampas grass species in Tasmania
and this species is self-fertilizing, so every plant is a problem.
It is now more than twenty years since the government sponsored pampas grass
eradication program of the 1990’s. Over time the public memory dims and it is forgotten
that so much money, time and effort has been invested in pampas eradication.
Considerable investment was made into raising public awareness, and trials were
conducted to learn the best methods for control, the most efficient time for control, along
with the most efficient herbicides. Eradication of pampas grass is achievable. However,
the problem has been reduced to “background noise” level, not too threatening but
costing money each year in on-going control. In addition the threat of a potential
explosion of pampas grass remains.
Pampas grass is no longer available through plant nurseries, therefore there is no
concern regarding the further introduction of plants to the region. In one sense the
problem is already contained, now the focus needs to be on stopping the spread from
plants already present.
In 2014 the pampas grass problem is now anticipated to be greater on publicly owned
property or commercially operated businesses such as quarries, mines and forest
operations rather than private gardens and farms which was the case in the 1990’s.
The success or failure of a “Pampas Eradication Project” will directly reflect the amount
of effort invested in it, and the ownership that land owners and managers take of the
problem.
A coordinated approach is seen as essential if there is going to be a successful effort to
locate, control and eventually eradicate pampas grass in the Cradle Coast Region.
A Project Officer with responsibility for the entire program and delivering a single
consistent message is most likely to achieve good results. This person should be a
Weeds Officer gazetted under the Weeds Management Act (1999), to enable the officer
to enforce compliance where necessary.
All land managers and the environmental officers of various utility services in the Cradle
Coast Region will need to be contacted, and many of their sites visited. Land managers
need to be re-acquainted with the perils of pampas grass. Education on best practice
control methods needs to be provided and accurate mapping of infestations needs to be
carried out. It may be necessary to help coordinate contract services to ensure a timely
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Pampas grass (Cortaderia spp.) Control Strategy for the Cradle Coast Region. 2014
result. A Project Officer could work with land managers to capture and share data on a
regional basis, and seek funding for coordinated control and monitoring.
8.0 RECOMMENDATIONS
1. A Project Officer dedicated to the “Pampas Eradication Project” needs to be
employed for at least 8 months of the year from October until May. The Project
Officer will liaise with all land managers in the Cradle Coast Region.
2. The Project Officer would need to be a gazetted Weeds Officer under the Weed
Management Act (1999).
3. The Project Officer would bring together representatives from all land
management agencies and the environmental officers of various utility services in
the Cradle Coast Region. This would be done through publicity as well as
networking and establishing an informal group of representatives from land
management agencies (Pampas grass Eradication Working Group). The group
can either meet face to face or as an email group. A letter of invitation to join the
group could be sent out and participants would be supported and kept informed
with current information by the Project Officer, as well as potentially receiving
some funding for pampas grass control. The group would also provide a forum
for information exchange and support from peers. The group would generate
energy and enthusiasm for the task of pampas grass control.
4. Coaching for all responsible persons would need to be carried out to refresh or
even train new operators of the approved control methodology, for example –
must remove flowering heads, must tape or gps location, must spray, must
monitor locations for several years.
5. The accurate recording of pampas grass locations followed by the collation of
this information into maps is a great tool for identifying “hot spots” and areas of
focus. Cradle Coast NRM rolled out Person Digital Assistance (PDA) units to the
nine municipalities in the Cradle Coast Region – this information capture will
boost the data base considerably.
6. Work with non-compliant land owners, and coordinate a contractor to do control
works on behalf of, and paid by, the land owners who are not achieving. (Once a
land owner had been requested by a gazetted Weeds Officer to remove a
declared weed, doing nothing is NOT an option. But many land owners are not
willing, able or competent to do the actual control works themselves… it would be
cheaper and easier for them to pay a contractor who will achieve the required
standard.)
7. At the end of each pampas grass season the Project Officer would collate all
data from all land managers and produce maps and upload into the Tasmanian
Natural Values Atlas (NVA).
8. Publicity is extremely important, the profile of pampas grass needs to be placed
front and centre of the public conscience at the start of the pampas grass
season. The timing varies depending on whether the area has C. reichardii and
C. selloana, or only C. jubata (which flowers later). Use the different media in a
variety of ways, articles in newspapers, interviews on radio, and advertisements
on television.
9. The “hotline” which the general public can use for reporting a pampas grass
sighting could include the weed app at Cradle Coast NRM, or phoning a landline
number, or social media.
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Pampas grass (Cortaderia spp.) Control Strategy for the Cradle Coast Region. 2014
10. Reward participants in the “Pampas Project” perhaps with a BBQ. Maps and
feedback can be provided to all participating bodies in the “Pampas Project”
regarding the “successes” and “areas to be improved”. Rather than a name and
shame approach the focus would be on recognition for diligence and effort.
11. Consider if this is a project which might fit the parameters of funding rounds
when they are offered. Field work requires some skill in GPS operation and
accreditation in chemical handling, but can be carried out by a small team. A
team has the benefits of safety in the bush as well as more eyes on the job
searching and controlling pampas grass plants.
9.0 GOALS, OUTCOMES AND ACTIONS
Table 1: Goals, Outcomes and Actions for the Pampas Grass Eradication Project
All land managers A coordinated
Best practice
A steady reduction
GOALS
accepting
approach to
control
of pampas
responsibility for
pampas grass
information and
numbers
pampas grass
control across all advice easily
/infestations, until it
control in the
land tenures
available to all
is ultimately
Cradle Coast
land managers
eradicated
Region
A project officer
Informed and
A concerted effort
OUTCOMES Land managers
confident that
co-ordinates the
aware land
towards achieving
eradication is
pampas grass
managers
pampas grass free
achievable
eradication
status
project
Land managers
No spread of
Improved public Land managers
are compliant with pampas grass
awareness
seeing infestation
Weed
from seed on
sizes diminish
Management Act
adjoining
1999
properties
Land managers
Sharing of data
Reporting
Preparedness
adopt a strategic
regarding “hot
system being
before pampas
approach to
spots” between
utilized by the
grass starts
pampas grass
land managers
public
flowering
control
Land managers
Emphasis on
Publicity blitz
Remove all
ACTIONS
actively participate mapping all
just prior to
flowering heads
in the Pampas
infestations
pampas grass
THE MINUTE they
Grass Eradication
flowering
are seen; double
Working Group
bag the flowers
Sharing of
Compilation of
Establish a
Thorough
mapping data
mapping data at
reporting
searching to find all
between working
the end of the
mechanism for
flowering plants
group members
season
the public
Feedback
Refresher
Monitoring of
mapping data to
course offered
controlled sites to
Pampas grass
to major land
ensure control
Eradication
managers on
methods are
Working Group
best practice
effective
control methods
prior to pampas
grass flowering
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Pampas grass (Cortaderia spp.) Control Strategy for the Cradle Coast Region. 2014
Effective control
of known pampas
locations using
the most benign
herbicides
10.0 CONTROL METHODS
Pampas grass tussocks can be difficult to locate when they are not flowering, particularly
because several native plants are very similar in appearance such as Gahnia grandis
(cutting grass). However the flower spike of pampas grass is distinctive. Be sure about
positive identification because pampas grass tussocks are quite cryptic in a bush setting
and blend in with other native grasses and sedges such as cutting grass (Gahnia
grandis), tall sedge (Carex appressa), and sword sedge (Lepidosperma sp.). There are
several identifying characteristics which make the identification of Pampas grass
tussocks easier even without the flowers:
•
•
•
•
•
•
•
The strap like leaves have a prominent mid-vein
The leaves have rough (cutting) edges and the underside of the mid-vein has fine
spines
The leaves curl into “pigtails” on the ends, and older leaves die at the base of the
tussock to form yellow, paper-dry “pigtails”
Different leaf colour at the base of the leaf clumps. Cutting grass tend to a dark
brown as the leaves get to the ground, while pampas remains bright green
tending to straw coloured
The flower stems on C. appressa are triangular, pampas grass flower stems are
round
Gahnia grandis does not have a prominent mid-rib on the leaves although the
leaves are strap-like, and Lepidosperma sp. leaves are thick, tough and straight.
Field workers also need to be able to identify the native southern reed
(Phragmites australis) which has a tall fluffy flower head.
Step 1
Preparation - start early - remind all land management agencies in spring where C.
reichardii or C. selloana is present to be ready for action. Where only C. jubata exists
remind land managers as soon as work commences in January after the Christmas
break to be ready for action.
Coach/refresh responsible officers on the best approach for successful control.
Coaching to include:
 ALWAYS carry bags to put cut off flower heads into and double bag the flower
heads;
 ALWAYS remove flower heads immediately. Remind officers that every flower
head which releases seed is creating more work next year and delaying the goal
of eradication.
 GPS the location, or at least put flagging tape on the pampas grass tussock.
Herbicide can be used at this stage or later, depending on land manager
agreement. Remove flower heads immediately if at all possible. The only excuse
is if it is not possible to access them.
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Pampas grass (Cortaderia spp.) Control Strategy for the Cradle Coast Region. 2014




Cut well down the flower head stem, flowers open slowly and if not enough stem
is removed the plant will still flower with a crew-cut!
When flower heads first emerge they are silky which means they are not yet
fertilized or releasing seed. This is the optimal time to remove flowers. If the
flower heads are dry and fluffy, then they are fertile and are even difficult to get
bagged without losing seeds. Extra care needs to be taken.
Do not leave the flower heads on and spray the plants - It takes only days for a
silky flower head to turn into a fluffy seeding one. Spraying the plant does not
disable the seed.
Active sites will need to be re-visited 2-3 times in a season. Not all pampas grass
plants flower at the same time.
Step 2
Visit all previously active pampas grass sites early and check for new plants. Flowering
may not have started but pampas tussocks and/or seedlings should be visible and early
monitoring of the known sites allows more time for attention to new outbreaks.
Step 3
Spray the plant after the flower heads have been removed. Previously in this strategy it
was mentioned that during the initial control program a number of different control
methods were tested. From this we learn that chemical control is more effective than
mechanical control, as long as spraying is conducted correctly.
 Herbicide: Glyphosate is cheap, relatively safe and easy to use, as
environmentally benign as possible for a chemical, and effective on pampas
grass. The recommended product is one of the “frog friendly” products such as
Round-up Biactive® or Weedmaster®. Use at the rate recommended for “hard to
kill” plants ie: 15 ml per litre. Do not be tempted to use at higher rates, or the risk
is that the foliage will burn off, without killing the roots! Ensure a complete
coverage of all foliage; if only half the plant is sprayed, only half the plant will die!
Remember pampas grass tussocks can be propagated by division of parent
tussocks, all parts of the tussock can grow independently.
If control of pampas plants occurs in or near water then the Guidelines for Safe and
Effective Herbicide Use Near Waterways (DPIPWE) needs to be consulted.
 Mechanical: Small plants can be hand pulled or grubbed out with a mattock but
remember to double bag any material with roots attached.
Step 4
It is necessary for Field Officers to have a Permit to Collect and Transport Declared
Weeds. Permits are available from the DPIPWE Regional Weeds Officer. The
appropriate method for collecting, transporting and disposing of pampas grass is to
place any flower heads or plant material containing roots in a strong bag inside another
bag to lessen the risk of a bag being punctured and broadcasting seeds. Bags should be
disposed of with deep pit burial.
If machinery is used for the removal of pampas grass it is necessary to clean down the
machine before it leaves the site following the Washdown Guidelines for Weed and
Disease Control (2004)
If new seedlings are appearing at a known site which is being controlled, then a
mother plant has been missed! New seedlings are not coming up from ground-
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Pampas grass (Cortaderia spp.) Control Strategy for the Cradle Coast Region. 2014
stored seed... there is a hidden flowering pampas. If all pampas grass plants are
controlled and not allowed to seed then eradication is complete after a 2-3 year
monitoring program.
Table 2: Timeline for the “Pampas Project” in the Cradle Coast Region
Time
Action – field
Actions – administrative
September – October
Recruit a Project Officer.
Project Officer contacts all
participants in the “Pampas
Project”, current mapping is
presented and field work
coaching day organized.
Project Officer trained as
Gazetted Weeds Officer
November - March
Re-visit known pampas sites
Organise some advertising
with GPS, bag and secateurs.
and a pampas hotline. Get all
C. reichardii
Spray any plants found, but
of the public’s eyes working for
C. selloana
ensure that any half formed
you!
flower heads are removed.
Contact all land-managers and
remind them to be active and
vigilant
December – March
Visit any new sites, with GPS,
Resource the pampas hotline,
bag and secateurs.
collecting the best location
information. Beware that
C. reichardii
Take good location
sites called in are usually in
C. selloana
information, remove flower
flower, and need to be
heads and spray plants if
possible. Follow-up with land- visited immediately! Landowner notification and
owner may or may not be
negotiation if necessary.
known.
January
Re-visit known pampas sites
Organise some advertising
with GPS, bag and secateurs.
and a pampas hotline. Get all
C. jubata
Spray any plants found, but
of the public’s eyes working for
ensure that any half formed
you!
flower heads are removed.
February – April
Visit any new sites, with GPS,
Resource the pampas hotline,
bag and secateurs.
collecting the best location
information. Beware that
C. jubata
Take good location
sites called in are usually in
information, remove flower
flower, and need to be
heads and spray plants if
possible. Follow-up with land- visited immediately! Landowner notification and
owner may or may not be
negotiation if necessary.
known.
May
Keep visiting late flowering
Resource the pampas hotline
sites, spray any uncontrolled
until May
sites.
Collate all of the hotline sites
Check the effectiveness of
for the database.
control operations
Collate all data from all
participating land-managers
Update maps and location
information for the following
year
Hold an “end of season” BBQ
to present maps and info to
participants in “Pampas
Project”
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Pampas grass (Cortaderia spp.) Control Strategy for the Cradle Coast Region. 2014
11.0 CASE STUDY
Circular Head Dolomite is an
encouraging case study. This large
open cut quarry is located on the
outskirts of Smithton. The quarry itself
is approximately 5 hectares
surrounded by a perimeter of native
scrub. Pampas grass growing in
nearby public and private gardens
invaded the quarry (remember pampas
loves disturbance and bare ground) in
the 1990’s and the infestation
escalated in size to cover 1000’s of
mature and juvenile plants. The image
opposite is indicative of the
inhospitable ground which can be
colonized by pampas grass. Access to
some flowering plants was so difficult
the local S.E.S group were used to
incorporate abseil training with pampas
grass control! For years seedlings kept
emerging which indicated the presence
of hidden seeding “mother plants”.
Pampas grass can be very cryptic
amongst native vegetation or even
around sheds and amongst
infrastructure.
Figure 4: Pampas grass plant in hard to access
Location in Circular Head Dolomite quarry.
Image: S. Jennings
The “lightbulb” moment for the Dolomite Quarry came when weeds officers managed to
convey the short timeframe required to control pampas if ALL seeding plants are
removed/sprayed/controlled. This resulted in more and more thorough searching of the
general area for a seed source. Eventually the “mother plants” were located, often
hidden in the surrounding scrub. This concerted effort by the managers of Circular Head
Dolomite over the past 5-6 years has seen the problem beaten, and control operations
clearing up the final few plants. Successful control has required several “search and
spray” monitoring visits each season. Timing has been important, with control of all
known areas taking place before flowering, ensuring that these plants do not set seed.
Flower spikes are only used to find plants in areas not already known. Congratulations
to Circular Head Dolomite for taking the problem seriously and accepting the
encouragement that eradication WAS possible.
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Pampas grass (Cortaderia spp.) Control Strategy for the Cradle Coast Region. 2014
11.0 REFERENCES
http://dpipwe.tas.gov.au/invasive-species/weeds/weeds-index/declared-weedsindex/pampas/pampas-control accessed 10 April 2014
Blood, K., (2003): Environmental Weeds – A field guide for SE Australia. Bloomings
Books, Melbourne, Australia
DPIWE: (2004): Tasmanian Washdown Guidelines for Weed and Disease Control,
Edition 1. Department of Primary Industries, Water and Environment.
DPIPWE: Guidelines for Safe and Effective Herbicide Use Near Waterways. Department
of Primary Industries, Parks, Water and Environment
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