Download NSW Far North Coast - Rous County Council

NOXIOUS WEEDS
nsw far north coast
CONTENTS
Why are weeds such a problem?..............................1
Plant physiology and ecology....................................2
About Rous County Council - Weed biosecurity........4
Control methods........................................................5
Detailed control techniques.......................................6
Weed classifications................................................10
Noxious weed declarations for the
NSW Far North Coast.......................................... 11
Aleman grass....... 16
Alligator weed....... 17
Bitou bush............ 18
Broad-leaf pepper
tree.................... 19
Cats claw creeper.. 20
Cecropia............... 21
Chinese celtis....... 22
Chinese tallow
tree.................... 23
Chinese violet....... 24
Eurasion water
milfoil................. 25
Giant devils fig...... 26
Green cestrum...... 27
Grounsel bush...... 28
Honey locust......... 29
Horsetail............... 30
Hymenachne........ 31
Kidney leaf mud
plantain.............. 32
Kosters curse....... 33
Kudzu................... 34
Miconia................. 35
Mikania vine......... 36
Mysore thorn........ 37
Paper mulberry..... 38
Parthenium weed. 39
Pond apple........... 40
Senegal tea plant.. 41
Siam weed............ 42
Tropical soda
apple.................. 43
Water lettuce........ 44
White blackberry/
Mysore raspberry.45
Witchweed............ 46
Yellow bells........... 47
How you can help....................................................48
Identify a weed........................................................49
Our contact details.................................... back cover
Cover (left to right from top): Cecropia, Kosters curse,
Alligator weed, Chinese tallow, Bitou bush, Giant devils fig.
WHY ARE WEEDS SUCH A
PROBLEM?
Traditionally weeds have been thought of as a problem of
the rural sector where they posed economic restraints on
the landholder.
In urban communities, weeds were considered a ‘nuisance’
rather than a hazard as they supposedly posed no
economic, environmental or health problems in those
areas.
During the last decade the community has become
more aware of problems associated with noxious weeds.
Increase in public concern about land degradation,
allergenic weeds and deterioration of the environment has
resulted in a shift in urban community attitudes regarding
noxious and environmental weeds.
The long-term solution to noxious weeds problems lies
with all stakeholders:
•
•
•
state government
local government
NSW Dept of Primary
Industries
•
•
•
•
statutory authorities
private landholders
Bushcare groups
the community
working together using effective and legal weed control
practices.
Cats claw creeper.
1
Plant Physiology and
Ecology
To have effective weed management, you need an
understanding of each weed’s physiology and ecology.
Weeds have optimal growing conditions of temperature,
light, moisture and soil types.
Weed dispersal and proliferation depends on the plant’s
ability to spread.
Each weed has a different combination of dispersal
methods; the rate of spread or dispersal may depend on:
•
•
•
•
•
•
2
wind
water, especially nutrified urban runoff
birds and animals
physical transplanting by human activities
rubbish dumping
inappropriate urban development
•
•
inappropriate fire regimes
movement by domestic, commercial and recreational
vehicles and heavy machinery.
Noxious weeds tend to have a broad geographical range
and non-specific environmental requirements. This allows
them to establish in a wide variety of habitats.
They may also produce large quantities of seed with high
viability and multiple dispersal vectors.
Understanding the reproductive capability, methods of
propagation and weed dispersal vectors is essential
to form a strategy for each species and thus minimise
reinfestation and further spread.
Left: Illegal dumping. Below: Broad-leaf pepper tree.
3
rous county council
Council’s weed biosecurity activities cover the Tweed,
Byron, Ballina, Lismore City, Richmond Valley and Kyogle
shires.
Rous County Council - Weed biosecurity, is the Local Control
Authority for noxious weeds in the Northern Rivers region.
Our goals are to:
•
Exclude new noxious weeds (prevent them establishing in
our region)
•
Eradicate or contain any new noxious weeds found in our
region (eliminate them or stop their spread)
•
Effectively manage the impacts of widespread invasive
noxious weeds species, and
•
Build capacity in our region to help the community, industry
and government commit to long-term management of
invasive noxious weeds.
To achieve this we focus on:
•
Identification and management of high-risk weed species
and how they spread into and within our region
•
Improving our capacity to find new weeds early
•
Ensuring we have the resources and procedures to take
rapid strategic control measures against new weeds in our
region
•
Directing our resources to where benefits will be the
greatest, and
•
Increasing community commitment and involvement in
proactive weed management.
4
CONTROL METHODS
Each of the following weed pages includes symbols
indicating which control methods, shown below, to use.
Hand removal
Suitable for plants that regrow from bulbs, tubers or
other plant parts (such as runners). Hand pull or dig the
seedlings.
Stem scrape
Suitable for vines and some woody plants. Scrape one
side of the stem to expose the growing layer; apply
glyphosate-based herbicide immediately to the scrape.
STEM INJECTION
Suitable for woody weeds and trees.
Cut and paint
Suitable for vines without aerial tubers. Cut all stems
and apply glyphosate-based herbicide immediately.
Cut stump
Suitable for woody plants. Cut the trunk and apply
glyphosate-based herbicide immediately.
Frill
Suitable for trees. Make horizontal cuts around the trunk
to depth of growing layer and apply glyphosate-based
herbicide immediately.
BASAL BARK SPRAYING
Suitable for thin-barked woody weeds and undesirable
trees.
Low volume spraying
Suitable for weeds that are less than 1m in height.
Spray with a herbicide that is registered for that weed.
Do not spray woody weeds, shrubs or vines over 1m in
height.
HIGH VOLUME SPRAYING
Suitable for most woody weeds shrubs or vines. Spray
with a herbicide that is registered for that weed.
B
Biological control
Biocontrol agents are available for this weed. For more
information, contact your local Council.
5
DETAILED CONTROL TECHNIQUES
USING HERBICIDES
Source: Noxious and environmental week control handbook 6th edition.
Herbicides are commonly used for controlling weeds in
agricultural and non-agricultural situations, and there are
many types of equipment and techniques available for
applying them. The appropriate option will be determined by
the size of the infestation, the available resources, access and
personal preferences. The most commonly used application
techniques are listed and described below. Always remember
to read the product label and any relevant permit before using
a herbicide.
Cut stump
Here the plant is cut off completely at its base (no higher than
15cm from the ground) using a chainsaw, axe, brushcutter
or machete (depending on the thickness of the
stem/trunk). Herbicide is then sprayed, squirted
or painted on to the exposed surface of the cut
stump emerging from the ground, killing the
stump and the root system.
It is imperative that the herbicide solution is
applied as soon as the trunk or stem is cut. A delay of more
than 15 seconds between cutting and applying the chemical
will give poor results. Two operators working as a team can
use this method effectively. The herbicide can be applied from
a knapsack, or with a paintbrush, drench gun or a hand spray
bottle. A coloured dye should be used in the solution to mark
the stumps that have been treated.
This method has the appeal of removing the weed
immediately, and is used mainly for trees and woody weeds.
Cut and swab
This method is similar to the cut stump method, but is suited
to vines and multi-stemmed shrubs. Here, the plant stems
are cut through completely, close to the ground. Herbicide is
then applied immediately to the cut surface emerging from the
ground, via spray or brush application.
In the case of Madeira vine and some other vines with aerial
tubers, both ends of the cut stems must be treated with
herbicide.
6
Always use herbicides according to the product label.
Contact Council for further information and advice on
spraying weeds with herbicide.
Stem-scraping
This method is also called bark-stripping or
stem-painting. Stem- scraping is used for plants
and vines with aerial tubers. A sharp knife is
used to scrape a very thin layer of bark from
a 15–30cm section of the stem. Herbicide is
then immediately applied to the exposed soft
underlying green tissue. In the case of Madeira
vine, all tubers within reach should be collected, removed and
composted or destroyed before starting the scraping.
With some woody weeds the bark can be peeled away and
the exposed wood painted or sprayed with herbicide.
Stem injection methods
Herbicide is placed immediately into holes or cuts made by
drilling or cutting through the bark into the sapwood tissue in
the trunks of woody weeds and trees. The aim is to reach the
sapwood layer just under the bark (the cambium), where the
chemical will be transported throughout the plant.
It is essential to apply the herbicide immediately (within 15
seconds of drilling the hole or cutting the trunk), as stem
injection relies on the active uptake and growth of the plant to
move the chemical through its tissues.
Stem injection methods kill the tree or shrub where it stands,
and only trees and shrubs that can be safely left to die and rot
should be treated this way. If the tree or shrub is to be felled,
allow it to die completely before felling.
Stem injection – drill and fill method
This method is for trees and woody weeds
with stems or trunks greater than 5cm in
circumference. A battery-powered drill
is used to make downward-angled holes in the sapwood
approximately 5cm apart. Herbicide is then injected in
measured doses using a backpack reservoir and syringe.
Stem injection – axe cut method
The axe cut method can be used for trees and woody weeds
7
with stems or trunks greater than 5cm in circumference. Using
an axe or tomahawk, horizontal cuts are made
into the sapwood around the circumference of
the trunk at waist height. While still in the cut,
the axe or tomahawk is leaned out to make
a downward angled pocket, which will allow
herbicide to pool.
The herbicide is then immediately injected into
the pocket. Cuts should be made no farther than 3cm apart.
This method is also referred to as frilling or chipping.
It is important not to entirely ringbark the trunk, as this will
decrease the uptake of the herbicide into the plant.
Tree spearing
Tree spearing is an alternative stem injection
method to the use of an axe or drill. The
method uses a specifically designed tree
spear and technique. The spear is thrust
into the tree at an angle of 30° to 40° from
the vertical, opening a cut in the tree and
applying the appropriate herbicide amount.
The process is repeated, forming a row of cuts approximately
50 mm apart.
Low volume spraying
Gas guns or splatter guns apply a low volume of high
concentration, translocatable herbicide
to the foliage of an infestation (generally
woody weeds). The herbicide is squirted
from a gas-powered gun, placing very
large droplets onto the leaves from 6–10m
away. The splatter is arched over the tops
of bushes and down their sides at specific
intervals (refer to product labels for exact rates). Only a small
portion of the foliage needs to be treated, minimising off-target
damage and reducing chemical usage. This technique allows
for specific targeting of the herbicide and a marker dye is
necessary to identify treated areas.
High volume spraying
High volume (foliar) spraying is the use of herbicide diluted
with water at a specific rate, and sprayed over the foliage to
the point of runoff (until every leaf is wetted, but not dripping).
8
It is suitable for shrubs, grasses and dense vines where
complete coverage can be achieved. Advantages include
speed of application and economy. Disadvantages include the
potential for spray drift and off-target damage.
Foliar spraying can be done a number of ways, depending
on the size of the weed plant and/or the infestation. Blanket
spraying using a boom spray mounted on a vehicle can be
used to treat large areas with infestations up to 1m in height.
Taller infestations, or those with difficult access, can be
sprayed with a handgun connected by a hose to a herbicide
tank and pump, carried by a tractor or vehicle. Smaller
infestations can be sprayed using a backpack/knapsack spray
unit. Spot spraying is treating individual weed plants, areas
that have only small clumps of weed infestations, or regrowth
areas.
Basal bark spraying
An oil-soluble herbicide is mixed with diesel and sprayed
around the full circumference of the trunk or stem of the
plant. It works for plants with basal diameters up to 10cm
and heights of 30 to 100cm (check herbicide product labels
as some plants can only be treated if their basal diameter is
less than 5cm). The diesel helps move the herbicide through
the bark and into the underground
storage organs of the plant, slowly
killing it.
The whole circumference of the
stem or trunk must be sprayed or
painted with herbicide solution from
ground level to a height of 30cm. It is
important to saturate the full circumference of the trunk, and to
treat every stem or trunk arising from the ground.
Basal bark spraying is suitable for thin-barked woody weeds
and undesirable trees, and is also an effective way to treat
saplings, regrowth and multi-stemmed shrubs and weeds in
inaccessible areas, such as steep banks. It creates little or
no spray drift or off-target damage, and will usually control
difficult-to-kill weeds at any time of the year, as long as the
bark is not wet or too thick for the diesel to penetrate.
9
WEED CLASSIFICATIONS
Noxious Weeds
The Noxious Weeds Act 1993 is an instrument serving
the protection of our environment, general health of the
community and agricultural production. Under the Act all
noxious weeds must be controlled. The act applies to all
landowners and occupiers.
Weeds of national significance
Thirty-two Weeds of National Significance (WoNS) have
been identified by Australian governments based on their
invasiveness, potential for spread and environmental,
social and economic impacts. A list of 20 WoNS was
endorsed in 1999 and a further 12 were added in 2012.
All WoNS are a priority for control in the Rous County
Council area regardless of whether they are a declared
noxious weed. These weeds are:
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•
•
•
•
•
•
•
•
•
•
•
•
•
•
African boxthorn
Alligator weed
Asparagus weeds
Athel pine
Bellyache bush
Bitou bush/boneseed
Blackberry
Bridal creeper
Brooms
Cabomba
Cats claw creeper
Chilean needle grass
Fireweed
Gamba grass
Gorse
Hymenachne
Lantana
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Madeira vine
Mesquite
Mimosa
Opuntioid cacti
(Prickly pear)
Parkinsonia
Parthenium weed
Pond apple
Prickly acacia
Rubber vine
Sagittaria
Salvinia
Serrated tussock
Silverleaf nightshade
Water hyacinth
Willows.
Environmental weeds
These have not been declared noxious, but it is still
important that environmental weeds be destroyed as they
can also affect human health, or can be invasive in the
natural environment, killing the native flora and reducing
the natural biodiversity. Native animals may also be
affected due to the loss of their natural habitat.
10
Noxious weed declarations
FOR NSW FAR NORTH COAST
The table below is taken from Weed Control Orders,
published in the NSW Government Gazette, which detail
weeds declared noxious in NSW under the Noxious Weeds
Act 1993. This lists the weed, control class and control
requirements for each species declared in a local control
area.
Legend
Class Explanation
1
The plant must be eradicated from the land and
the land must be kept free of the plant. Owners or
occupiers of land must notify Rous County Council
- Weed biosecurity within 24 hours of becoming
aware that the weed is present.
2
These plants must be eradicated from the land and
the land must be kept free of the plant. Owners or
occupiers of land must notify Rous County Council
- Weed biosecurity within 24 hours of becoming
aware that the weed is present.
3
The plant must be continuously suppressed and
destroyed.
4
The growth of the plant must be managed in a
manner that continuously inhibits the ability of the
plant to spread and the plant must not be sold,
propagated or knowingly distributed.
4*
The plant must not be sold, propagated or
knowingly distributed.
5
Owners or occupiers of land must notify their local
control authority (Rous County Council - Weed
biosecurity) within 24 hours after becoming aware
of the unnatural spread of these weeds on land, or
the sale of same.
Common name
Botanical name
African boxthorn
African feather grass
Lycium ferocissimum
Cenchrus macrourus or
Pennisetum macrourum
Sisymbrium runcinatum and
Sisymbrium thellungii
Echinochloa polystachya
Alternanthera philoxeroides
Eichhornia azurea
African turnip weed
Aleman grass
Alligator weed
Anchored water
hyacinth
Class
4*
5
5
2
2
1
11
Common name
Botanical name
Annual ragweed
Ambrosia artemisiifolia
5
Arrowhead
Sagittaria calycina variety
calycina (syn. Sagittaria
montevidensis subspecies
calycina)
Cynara cardunculus
Asparagus virgatus (syn.
Protasparagus virgatus)
Tamarix aphylla
Xanthium species
4*
Festuca gautieri or Festuca
scorparia
Jatropha gossypiifolia
Chrysanthenoides monilifera
subspecies rotundata
5
Chrysanthenoides monilifera
subspecies rotundata
Rubus fruticosus
Centaurea xmoncktonii
Salix nigra
Chrysanthemoides monilifera
subspecies monilifera
Asparagus asparagoides (syn.
Myrsiphyllum asparagoides,
Asparagus medeoloides)
Asparagus declinatus
(syn. Asparagus crispus,
Myrsiphyllum declinatum)
Schinus terebinthifolius
3
Artichoke thistle
Asparagus fern
Athel tree / Athel pine
Bathurst, Noogoora,
Hunter, South
American, California/
cockle burrs
Bear-skin fescue
Bellyache bush
Bitou bush – Ballina,
Byron, Lismore
Kyogle and Richmond
Valley
Bitou bush – Tweed
Shire
Blackberry
Black knapweed
Black willow
Boneseed
Bridal creeper
Bridal veil creeper
Broad-leaf pepper
tree
Broomrapes
Burr ragweed
Cabomba
Camphor laurel
Cat’s claw creeper
Cayenne snakeweed
Cecropia
Chilean needle grass
Chinese celtis
12
Class
5
2
5
4
2
4
4
1
4
1
4*
1
3
Orobanche species except
the native O. cernua variety
australiana and O. minor
1
Ambrosia confertiflora
All Cabomba species except C.
furcata
Cinnamomum camphora
Dolichandra unguis-cati (syn.
Macfadyena unguis-cati)
Stachytarpheta cayennensis
Cecropia species
Nassella neesiana
Celtis sinensis
5
5
4
4
5
2
4
4
Common name
Botanical name
Chinese tallow tree
Chinese violet
Triadica sebifera
Asystasia gangetica subspecies
micrantha
Climbing asparagus
Asparagus africanus (syn.
Protasparagus africanus)
Clockweed
Oenothera curtiflora or Gaura
parviflora
Cockspur coral tree
Erythrina crista-galli
Corn sowthistle
Sonchus arvensis
Dodder
All Cuscuta species except the
native species C. australis, C.
tasmanica and C. Victoriana
East Indian hygrophila Hygrophila polysperma
/ Hygro
Espartillo
Achnatherum brachychaetum
Eurasian water milfoil Myriophyllum spicatum
Fine-bristled burr
Cenchrus brownii
grass
Fireweed
Senecio madagascariensis
Flax-leaf broom
Genista linifolia
Fountain grass
Pennisetum setaceum
Frogbit / Spongeplant Limnobium laevigatum and L.
spongia
Gallons curse
Cenchrus biflorus
Gamba grass
Andropogon gayanus
Giant devils fig
Solanum chrysotrichum
Giant rats tail grass
Sporobolus pyramidalis
Giant reed / Elephant Arundo donax
grass
Glaucous star thistle
Carthamus glaucus
Golden thistle
Scolymus hispanicus
Green cestrum
Cestrum parqui
Grey sallow
Salix cinerea
Ground asparagus
Asparagus aethiopicus (syn.
Protasparagus aethiopicus)
Groundsel bush
Baccharis halimifolia
Harrisia cactus
Harrisia species
Hawkweed
Honey locust
Horsetail
Hydrocotyl / Water
pennywort
Hygrophilia
Hymenachne
Karoo thorn
Class
3
1
2
5
4
5
5
4
5
1
5
4*
4*
5
1
5
5
3
3
4*
5
5
3
2
4*
3
4
Hieracium species
Gleditsia triacanthos
Equisetum species
Hydrocotyle ranunculoides
1
3
1
1
Hygrophilia costata
Hymenachne amplexicaulis and
hybrids
Acacia karroo (syn. Acacia
karroo)
2
1
1
13
Common name
Botanical name
Kidney leaf mud
plantain
Kochia
Heteranthera reniformis
1
Bassia scoparia (syn. Kochia
scoporia) except B. scoparia
subspecies trichophylla
Clidemia hirta
1
Pueraria lobata
Lagarosiphon major
Lantana species
Egeria densa (syn. Elodia
densa)
Phyla canescens
Ludwigia longifolia
3
1
4
4*
Berberis lomariifolia (syn.
Mahinia lomariifolia)
Nassella tenuissima (syn. Stipa
tenuissima)
Argemone mexicana
3
Miconia species
Mikania micrantha
Mimosa pigra
Asparagus macowanii
Genista monspessulana
1
1
1
2
3
Cenchrus echinatus
Bryophyllum daigremontianum
(syn. Kalanchoe
daigremontiana); B.
delagoense (syn. K.
delagoense, B. tubiflorum,
K. tubiflora); B. xhoughtonii
(syn. K. xhoughtonii, B.
daigremontianumx, B.
delagoense, daigremontianumx,
B. tubiflorum, K.
daigremontianax, K. tubiflora);
B. pinnatum (syn. K. pinnata, B.
calycinum); B. proliferum (syn.
K. prolifera)
Caesalpinia decapetala
Cortaderia species
Broussonetia papyrifera
Parthenium hysterophorus
Amnona glabra
5
4
Vachellia nilotica (syn. Acacia
nilotica)
1
Kosters curse /
Clidemia
Kudzu
Lagarosiphon
Lantana
Leafy elodea / Dense
waterweed / Egeria
Lippia
Long-leaf willow
primrose
Mahonia / Chinese
holly
Mexican feather grass
Mexican poppy
Miconia
Mikania vine
Mimosa
Ming asparagus fern
Montpellier broom /
Cape broom
Mossman river grass
Mother of millions
Mysore thorn
Pampas grass
Paper mulberry
Parthenium weed
Pond apple
Prickly acacia
14
Class
1
4*
2
1
5
3
4
2
1
1
Common name
Botanical name
Prickly pear
Cylindropuntia species
4
Prickly pear
Opuntia species except O.
ficus-indica
Ligustrum ludicum
Ligustrum sinense
4
Oryza rufipogon
Toxicodendron succedanea
Cryptostegia grandiflora
Sagittaria platyphylla (syn.
Sagittaria graminea variety
platyphylla)
Salvinia molesta
Cytisus scoparius
Gymnocoronis spilanthoides
Nassella trichotoma
Chromolaena odorata
Asparagus falcatus
Brassica barrelieri subspecies
oxyrrhina
Picnomon acarna
Centaurea maculosa
Hypericum perforatum
Helianthus ciliaris
Solanum viarum
Trapa species
Pistia stratiotes
Stratiotes aloides
Rubus niveus
5
4
1
4*
Salix species except S.
babylonica, S. xreichardtii. S.
xcalodendron, S. cinerea and
S. nigra
Striga sp. except native sp. and
Striga parviflora
Tecoma stans
Limnocharis flava
Cyperus esculentus
4*
Privet (broad-leaf)
Privet (narrow-leaf /
Chinese)
Red rice
Rhus tree
Rubbervine
Sagittaria
Salvinia
Scotch broom
Senegal tea plant
Serrated tussock
Siam weed
Sicklethorn
Smooth-stemmed
turnip
Soldier thistle
Spotted knapweed
St Johns wort
Texas blueweed
Tropical soda apple
Water caltrop
Water lettuce
Water soldier
White blackberry /
Mysore raspberry
Willows
Witchweed
Yellow bells
Yellow burrhead
Yellow nutgrass
Class
4
4
4
4*
1
4
1
2
5
5
1
4
5
1
1
1
1
3
1
3
1
5
Declarations list correct as of November 2014
15
aLEMAN GRASS
Echinochloa polystachya
Class
2
Aleman grass is an aquatic or semi-aquatic perennial grass
growing to between 1-3m high.
Summer flowering, the flower heads are 15-30cm long. Seed
production is poor and most spread is vegetative, occurring
when stems, runners and roots are moved in water. Growth
and localised spread depends on fluctuating water levels.
When water levels drop, plants fall over and new shoots are
produced from the nodes of decaying stems. Each new shoot
then produces an individual plant that continues to grow as
water levels rise. Shoots can grow from any node.
EFFECTS ON THE ENVIRONMENT
Aleman grass will quickly replace native aquatic species,
forming a monoculture. It is a serious threat to the wetland
and floodplain areas of tropical Australia. Large areas of open
water are also at risk of invasion, potentially impacting on
fisheries and waterbird habitat.
HABITAT
Aleman grass originates from tropical and subtropical
America. It was introduced to Queensland as a ponded
pasture species and now invades seasonally flooded areas,
swamps, and banks of watercourses.
It has been recognised as a serious crop weed in India,
Mexico and Argentina. In southern USA, it is a significant
weed of rice crops and crayfish production. It is also
considered a weed in Hawaii, Sri Lanka, Chad and Zaire.
It forms dense stands in swampy areas and along banks of
watercourses and is able to grow in water up to 2m deep.
CONTROL METHOD
16
ALLIGATOR WEED
Class
2
Altemanthera philoxeroides
* WEED OF NATIONAL SIGNIFICANCE *
Alligator weed is an aquatic and terrestrial perennial herb.
Large mats of interwoven stems develop from plants near
stream banks and extend over the water surface. Its stems
are green-brown, 10-70cm long and hollow with leaves that
are dark green, opposite, obovate/narrow-elliptical 2-7cm
long and 5-40mm wide. Roots produced at the nodes attach
to soil and hang in water. Flowers are papery white, in a
rounded compact spike, which is borne on a peduncle up to
3cm long rising from the leaf axils. Propagation occurs from
stem fragments. Growth and regrowth commences in early
spring with rapid growth during summer. As winter approaches
emergent stems lose their leaves and, becoming prostrate,
thicken the vegetative mat providing the base for the next
season’s growth.
EFFECTS ON THE ENVIRONMENT
Alligator weed has been described as one of the world’s
worst weeds, due to its vigorous growth habit and its ability
to establish in both aquatic and terrestrial forms. The weed’s
potential impacts on natural aquatic systems, the agricultural
industry and urban drainage systems are enormous. Control
is costly and requires ongoing treatment of infestations over a
number of years.
HABITAT
It thrives in shallow drainage ditches, canals, rivers, lakes,
reservoirs, swamps and wet or occasionally inundated
pastures.
CONTROL METHOD
B
17
BITOU BUSH
Class
3&4
Chrysanthemoides monilifera
ssp rotundata
* Weed of National Significance *
Class 3: Tweed Shire.
Class 4: Ballina, Byron, Lismore, Kyogle and Richmond Valley.
A perennial sprawling shrub, 1-2m high. Leaves are alternate,
bright green, usually smooth-edged or only slightly toothed
and pointed at the tip, and practically hairless although young
leaves have a cottony down. Flowers bright yellow with 1113 petals. The plant flowers intermittently all year, but main
flowering is May-July. Berries hang in clusters; during ripening
the green fleshy berries turn black. Seeds can be spread by
birds, foxes, ants and rabbits.
EFFECTS ON THE ENVIRONMENT An effective coloniser on sandy soils, it quickly dominates
existing vegetation, forming almost pure stands in many areas
to the detriment of native flora and fauna species. Dense
stands impede traffic along paths and can alter natural fire
regimes. Pest animals such as rabbits and foxes shelter in
large stands and compete with native animals for resources.
The dominant weed of coastal vegetation in NSW, it is
listed as a key threatening process to biodiversity under the
Threatened Species Conservation Act (1995).
HABITAT
Bitou bush has become an aggressive invader of Australian
native coastal ecosystems and is not restricted by climate.
It prefers sandy or medium textured soils and disturbed
situations, particularly near the sea where it tolerates saline
conditions. Recorded up to 10km inland, and occasionally
occupies disturbed edges and roadsides close to the coast.
CONTROL METHOD
18
B
Broad-leaf Pepper Tree
Schinus terebinthifolius
Class
3
A broad-topped, fast growing, multi-stemmed shrub or small
tree 1-6m tall. Plants are male or female and have leaves that
are alternate, dark green, with 4-12 opposite leaflets and a
terminal leaflet. Leaves often have a winged midrib. Flowers
small and greenish yellow. Female flowers are followed by
clusters of green berries that turn red when ripe 4-5mm wide
and contain a single kidney-shaped seed. Leaves and berries
have a pepper smell, especially when crushed, and may be
toxic to humans and animals.
EFFECTS ON THE ENVIRONMENT
Invades native vegetation and disturbed areas to form dense
stands and dominate understorey vegetation. Out-competes
and replaces native grasses, ground covers and shrubs. Shade
tolerant. Spreads rapidly on waterlogged or poorly drained soils,
but will grow on drier land in higher rainfall areas. Contains toxic
resins; related to the rhus tree and poison ivy. Some people
suffer severe itching, lesions, rashes, reddening, swelling of
the face, running sores and welts associated with the sap and
flowering trees. Rarely eaten by livestock but reportedly toxic to
some animals and birds.
HABITAT
Has potential to become a major environmental weed,
particularly in damp coastal areas, along banks of waterways,
mangroves, open forests and sand dunes. Grows in most
circumstances, full sun or heavy shade, moist or dry
conditions and thrives in disturbed or moist shady sites in
riparian areas. Bats and many introduced birds eat the fruit as
a staple food.
CONTROL METHOD
19
Cats Claw Creeper
Dolichandra unguis-cati
Class
4
* WEED OF NATIONAL SIGNIFICANCE *
A perennial climber, forming thick masses with woody stems.
Stems extend 20+ metres with a three-pronged tendril 1015mm long with stiff tips that form hooks (like a cat’s claws)
that aid in climbing. Large yellow trumpet flowers in clusters,
flowering in spring. Roots are much branched and produce
tubers at intervals along their length that can be up to 40cm
long; each can produce multiple stems. Winged seeds 2-4cm
long in a capsule 15-45cm long.
EFFECTS ON THE ENVIRONMENT
A serious weed that will smother large trees and shrubs.
Especially troublesome along coastal and hinterland streams
in Queensland and northern NSW. Due to the huge quantities
of seed produced and reproducing vegetatively, it has potential
to become a major weed, particularly in urban bushland along
the east coast.
HABITAT
The plant communities in Australia most commonly invaded
by Cats claw creeper are riparian zones and sub-tropical
and tropical rainforests, including Littoral Rainforest and
Riverflat Eucalypt Forest on coastal floodplains (Endangered
Ecological Communities) that are found in Sutherland Shire.
Most surviving remnants of these communities are small
and particularly prone to weed invasion and degradation.
Cats claw creeper grows in a range of soil types, but does
not tolerate poorly drained soils. Plants are capable of
surviving heavy frost but seed germination is reduced at low
temperatures.
CONTROL METHOD
20
CECROPIA
Cecropia species
Class
2
Common names include Trumpet tree and Snakewood.
Native to tropical Central America, this plant can grow up to
25m. The plants can be distinguished by the large U-shaped
leaf scars on the stems and the alternate, deeply-lobed leaves
(similar to Pawpaw), 10-50cm wide. The surface is densely
covered with white hairs, and petioles are usually 23-30cm
long.
Hollow stems, flowers and fruits are the key features. Yellow
flowers are arranged in clusters of spikes, 12-18cm. Fruit is
cylindrical, ovoid to oblong-ovoid, somewhat flattened, 3.33.7cm long, with soft sweet flesh around many small seeds.
The plant matures in 3-5 years, and recorded to flower as
early as 3.3 years of age. Flowers are wind-pollinated and
produce about 18% viable seeds.
EFFECTS ON THE ENVIRONMENT Cecropia plants produces millions of seeds per plant that can
be dispersed by fruit bats and birds, giving it the potential
to invade forest ecosystems, possibly causing serious and
irreversible damage to our natural forests.
HABITAT
Cecropia species are among the most abundant weed
species across large parts of Central America and are quick
to colonise open, disturbed sites, as well as forests that have
been damaged by cyclones.Naturalised specimens are most
likely to be found in wetter habitats, such as riparian zones
and dry rainforest remnants.
CONTROL METHOD
21
CHINESE CELTIS
Class
4
Celtis sinensis
A semi-deciduous tree or tall spreading shrub to 20m high
with smooth grey bark. Chinese celtis has oval-shaped leaves
that are 4.5-9cm long with a pointed tip and toothed margins
along the upper half with sparse hairs along the midvein.
Cream flowers develop in early summer producing thousands
of round green fruits 7-8mm that turn orange in late summer/
early autumn.
EFFECTS ON THE ENVIRONMENT
Chinese celtis produces fruit and flowers prolifically. This
ensures that the dispersal is carried out over large distances,
with the assistance of feeding birds, water and other animals.
Chinese celtis plants will grow in dense colonies, infesting and
overpowering native bushland. The thick canopy of the plant
shades native plants from sunlight and the plants themselves
vigorously compete with native plants for water and nutrients
in the surrounding area. The seeds also have the ability to
germinate under heavy shade.
HABITAT
Chinese celtis has become a major environmental weed,
particularly widespread in damp coastal areas, along banks
of waterways, near rainforest and on clay soils in Western
Sydney. It grows in most circumstances, full sun or heavy
shade, moist or dry conditions and thrives in disturbed or
moist shady sites on riverbanks. Bats and many introduced
birds eat the fruit as a staple food.
CONTROL METHOD
Photo: Sutherland Shire Council
22
CHINESE TALLOW TREE
Triadica sebifera
Class
3
Chinese tallow is native to south-eastern Asia, mainly China,
and was introduced as an ornamental tree in streetscapes and
gardens. It is spread by humans through plantings, by birds,
and by water carrying the floating seeds.
It is easily recognised by its alternate heart-shaped leaves that
turn red in autumn before falling in winter. Its fruits split open
to reveal white-coated seeds that are sometimes likened to
popcorn, hence its other common name: Popcorn tree.
It is a medium to large tree that can reach 15-20m high.
Flowers between late spring and early summer, usually from
around November to February.
EFFECTS ON THE ENVIRONMENT
Chinese tallow produces up to 100,000 seeds per tree per
year with long seed dormancy. Shade, sun, drought and flood
tolerant, it can quickly establish thickets and displace other
vegetation and restrict access to waterways and wetlands.
This weed is invasive and alters nutrient cycles, quickly forming
dense monocultures displacing native vegetation.
HABITAT
While the Chinese tallow appears to favour wetter areas
such as swamps, they can grow in drier conditions and have
been planted as an ornamental tree in streets and gardens.
Infestations can be found throughout the North Coast of
NSW, with heavier infestations in the Casino area, and is also
present in other areas of NSW, Victoria and Queensland.
CONTROL METHOD
23
cHINESE vIOLET
Class
1
Asystasia gangetica
subspecies micrantha
Chinese violet is native to India, the Malay Peninsula and
Africa. It is a major weed overseas, notably in Malaysia,
Indonesia and the Pacific islands, where it infests crops such
as rubber and coffee, but particularly palm oil plantations.
The subspecies has become invasive in Australia, with its first
recording as naturalised made in NSW, north of Newcastle, in
1999. It is now known to occur in a number of nearby locations
and was found at South West Rocks near Kempsey on the
NSW Mid North Coast in 2009.
Chinese violet grows in mats similar to Wandering dew. On its
own it will grow to 1m high or over, shrubs up to 3m tall.
Leaves and stems have scattered hairs and are paler below.
Flowers 20–25mm long, white outside and inside with some
purple blotches in two parallel lines inside. The fruit is 3031mm long, guitar shaped (with neck of guitar attached to
stem) and containing four flattened seeds held in place by
conspicuous hooks. Plants spread by seed and/or rhizomes.
The seeds are dispersed explosively from drying capsules,
but long distance dispersal is generally by man. Stems root at
each node.
EFFECTS ON THE ENVIRONMENT
It can smother all vegetation in the herbaceous layer.
HABITAT
This weed grows in tropical and subtropical areas and
threatens biodiversity in these areas.
Notifiable weed. Call Council for assistance.
Photo: J Hosking
24
Photo: Graham Pritchard
Eurasion water milfoil
Myriophyllum spicatum
Class
1
Eurasian water milfoil is native to Europe, Asia and northern
Africa. This species has not been recorded as present in NSW
or elsewhere in Australia.
It spreads mostly via plant fragments that are spread over
long distances by water currents, and are mainly dispersed
between water bodies by boating and fishing activities.
A submerged perennial plant with stems that are rooted at the
base and grow towards the surface, it can grow in water from
0.5 to 10m deep, but most commonly at depths up to 3m.
The olive-green leaves are submerged and feather-like. They
grow in whorls of four around the stem with an average of 12
pairs of divisions.
Flowers are small and pinkish with four petals, occurring in
whorls of four around the stem.
EFFECTS ON THE ENVIRONMENT Eurasian water milfoil is a highly aggressive aquatic weed that
can spread rapidly. It forms a dense stand that shades out and
replaces all other aquatic plants, seriously impacting on native
plant and animal life. Dense mats also interfere with other
uses of water bodies, such as recreation and irrigation.
HABITAT
Eurasian water milfoil prefers lakes, ponds, shallow reservoirs
and slow moving water, but will also grow in fast moving water.
It can tolerate and thrive in a range of temperatures and water
conditions, including low levels of salinity.
Notifiable weed. Call Council for assistance.
25
GIANT DEVILS FIG
Class
3
Solanum chrysotrichum
Originating in Central America and introduced to the Far North
Coast of NSW around 35 years ago, Giant devils fig has since
been spread by birds and bats to become a serious weed threat
on the North Coast.
Giant devils fig is an erect perennial shrub up to 4m high. Large
leaves with 7-13 lobes divide halfway up.
The white star-shaped flowers have five petals and are hairy on
the outer surface. Flowering is autumn to spring.
The downward-facing thorns on the trunk are present from
when the plant is very young, which makes hand pulling
dangerous.
It has a small round green seed similar to that of a Wild
tobacco, which turns yellow when ripe.
EFFECTS ON THE ENVIRONMENT
Naturalising in disturbed habitats, creek banks, forests and
riparian areas, Giant devils fig is rapidly becoming a serious
threat to native vegetation and is suspected of poisoning
livestock. Its sharp thorns can inflict injuries on both animals
and people.
HABITAT
A weed of watercourses (i.e. riparian areas), closed forests,
forest margins, roadsides, parks, gardens, disturbed sites and
waste areas.
CONTROL METHOD
26
GREEN CESTRUM
Cestrum parqui
Class
3
Green cestrum is a medium-sized perennial shrub growing
to 2-3m high. Its shiny green leaves are 20-30mm wide and
80-100mm long. They have smooth edges, are pointed at
each end and are arranged alternatively along the branch.
The leaves have a foul smell when crushed. The flowers are
greenish yellow and common throughout most of the year,
but main flowering is from late spring to autumn. The flowers
occur in clusters at the end of branches and individual flowers
are 20-25mm long, and are trumpet in shape, opening into
five, six or seven small triangular lobes. Clusters of shiny
black egg-shaped berries 7-10mm long are produced during
summer and autumn.
EFFECTS ON THE ENVIRONMENT
Green cestrum is found in urban bushland growing in small to
medium size thickets, with larger infestations on alluvial soils
along streams. These infestations are usually dominant and
will exclude all other plants, including natives. The plant is
known to be toxic to livestock and humans. Death from eating
small quantities of leaves, twigs or fruit is usually rapid and
painful.
HABITAT
Green cestrum was previously found in large numbers around
horse stables and it has been a common garden plant.
Cestrum is now most commonly found in moist drainage lines
and bushland edges.
CONTROL METHOD
27
GROUNDSEL BUSH
Baccharis halimifolia
Class
3
Groundsel bush is a densely-branched shrub, usually 1.5-3m
high.
Leaves are dull or pale green, waxy to touch, alternate,
2.5-5cm long, 1-2.5cm wide, wedge-shaped and prominentlytoothed.
The male trees have cream flowers that occur in globular
heads. Female trees have white flowers that grow in head
clusters at the ends of branches.
Mature bushes have a deep branching taproot with numerous
fibrous lateral roots.
It was first introduced into Australia as an ornamental plant,
and by 1900 had become naturalised in Queensland.
Present in the Tweed, Richmond and Clarence catchments in
Northern NSW since the mid 1960s, it has gradually spread
southwards along the coastal fringe to the Taree area. It is
likely that Groundsel bush will spread further in Australia.
EFFECTS ON THE ENVIRONMENT
Groundsel bush is both an environmental and a forestry weed.
Thick stands can inhibit the movement of stock and reduce the
productivity and carrying capacity of agricultural land.
Each female plant can produce more than 1.5 million seeds
annually. Under windy conditions during flowering, seed can
be transported over long distances.
HABITAT
Groundsel bush is found in humid warm-temperate to
subtropical regions. It is mostly found in disturbed areas such
as coastal swamps, degraded pastures and forests where the
understorey has been removed.
CONTROL METHOD
28
HONEY LOCUST
Gleditsia triacanthos
Class
3
A deciduous, leguminous tree growing to 25m tall. Leaves are
dark green, about 10cm long with around 20 opposite paired
leaflets. In spring it produces a creamy-yellow flower that
develops into a 20-30cm long flat brown/black pod; each pod
can contain up to 30 seeds. The plant reproduces prolifically,
and stockes relish the legume’s seed pods. The trunk and
limbs of the Honey locust tree are covered in very sharp
needle-like spines that can grow to over 50mm in length.
EFFECTS ON THE ENVIRONMENT
Due to the enormous quantities of seed produced, drought
tolerance, fast growth and freedom of disease and pests,
Honey locust has the potential to become a major weed,
particularly in urban bushland and disturbed areas. Honey
locust smothers desirable vegetation, which reduces pasture
stocking rates and native regeneration. It forms dense thickets
that can block access by humans and stock, but harbour feral
animals such as rabbits, foxes and deer. When dense, these
weeds increase the risk of bushfire through increased fuel
load. The seed is spread by animals eating pods and passing
seed in dung, water transporting the floating pods, and
humans planting it as an ornamental plant or for fodder.
HABITAT
Honey locust often becomes dense on river banks, hillsides,
forest margins, roadsides and other disturbed areas. It will
also invade pastures and native vegetation. It is able to grow
on a wide range of soil types and climates.
CONTROL METHOD
29
HORSETAIL
Equisetum species
Class
1
Horsetails are non-woody herbaceous plants, native to the
northern hemisphere, including Europe, Northern America and
Asia. They are now naturalised in New Zealand, Madagascar
and parts of South America.
They have been grown and sold as ornamental plants in
Australia, and in the past have been sold at local North Coast
markets.
Plants usually spread by rhizomes that produce new stems
(shoots) throughout the growing season from spring to
autumn. Small parts of the rhizomes from mature plants can
break off and grow into new plants. Horsetails also produce
spores that require prolonged periods of moist conditions to
germinate successfully.
EFFECTS ON THE ENVIRONMENT
Highly invasive primitive plants, Horsetail is the common
name used to refer to 30 species in the Equisetum genus, 12
of which are considered weeds around the world. Common
horsetail (Equisetum arvense) and Scouring rush horsetail
(Equisetum hyemale) are of most concern in Australia. In high
densities they also reduce crop yields by producing inhibitory
substances that depress the growth of neighbouring plants. All
except the common Horsetail are toxic to livestock.
HABITAT
Horsetails are mostly found in wet areas such as the banks
and edges of swamps, rivers and lakes. They tolerate low
nutrient levels and grow in many soil types, usually in damp
conditions in open woodlands, pastures, stream banks,
embankments, arable land and roadsides.
Notifiable weed. Call Council for assistance.
Photo: B Trounce
30
HYMENACHNE
Hymenachne amplexicaulis
and hybrids
Class
1
* WEED OF NATIONAL SIGNIFICANCE *
Hymenachne is considered one of Australia’s worst weeds.
Native to the tropics of South and Central America, it is a
serious weed in Australia, the West Indies, Indonesia, the
Florida wetlands of USA and Suriname. Small infestations
have been found on the North Coast.
An erect grass that can grow in water up to 2m deep, it prefers
swampy situations such as river banks and seasonally flooded
areas. Submerged stems quickly produce roots from nodes.
A distinctive characteristic is the base of the leaf blade that
clasps around the stem.
The plant flowers in summer and autumn.
In NSW, it only reproduces by broken stem fragments and
stolons. Broken fragments of plant can be carried to new
locations by floodwater and will take root in moist soil. It
thrives in nutrient-rich water.
Flood waters also transport fragments into waterways,
irrigation storage facilities, sugar cane crops and natural
wetlands.
EFFECTS ON THE ENVIRONMENT
It forms dense infestations, displaces native plant species,
reduces biodiversity and threatens native wetland habitat.
HABITAT
Originally introduced to Queensland and the Northern Territory
as a ponded pasture species, it has invaded freshwater
wetlands, floodplains and river banks.
Notifiable weed. Call Council for assistance.
31
KIDNEY LEAF MUD PLANTAIN
Heteranthera reniformis
Class
1
Kidney leaf mud plantain is a sprawling annual or perennial
aquatic plant. The leaves are kidney-shaped, bright green and
glossy, up to 5cm wide and arranged alternately along the
stem. They are attached to a stalk 2-13cm long and are either
floating or emerging above the water.
It was introduced to Australia as an ornamental pond plant
and has been actively promoted on a number of Australian
websites.
The main method of dispersal is through vegetative
reproduction. Any stem fragment containing one or more
nodes is capable of producing a new plant. Plant fragments
can be washed downstream or moved to a new location in
mud stuck to animals or vehicles.
The plant is 20-50cm tall and grows in fresh water less than
15cm deep and on damp soil at the water’s edge.
EFFECTS ON THE ENVIRONMENT
It is able to form dense mats and colonise open shallow water,
such as disturbed wetlands and flooded rice production. Such
characteristics make this weed a potential threat to native
vegetation and freshwater aquatic habitats.
HABITAT
Kidney leaf mud plantain will quickly colonise open sunny
areas, but does not grow well in shaded areas or amongst
taller growing vegetation such as sedges and tall grasses.
It is most commonly found along roadside ditches, streams,
ponds, drains, freshwater tidal mudflats and riverbeds.
Notifiable weed. Call Council for assistance.
32
KOSTERS CURSE / CLIDEMIA
Clidemia hirta
Class
1
Kosters curse is a bushy perennial shrub native to tropical
America. Covered in reddish-brown bristly hairs it generally
grows to about 2m tall. Leaves are hairy and occur in opposite
pairs along the stem. The upper surfaces are a bright, shiny
green, and the undersides are paler. Five prominent veins run
down the length of the leaf, with many obvious cross veins
occurring between.
Clusters of 6-20 small flowers with five white or pinkish petals.
Flowers occur all year, except in dry conditions. Each flower
produces a reddish purple berry that is hairy and turns dark
purple when mature.
It has the potential to spread rapidly over many areas of
Australia where conditions are suitable, including the Northern
Territory, Northern NSW, and much of northeast Queensland.
In 2001, an infestation was found near Julatten, north
Queensland.
EFFECTS ON THE ENVIRONMENT
Kosters curse is a highly invasive shrub, forming dense
thickets that can smother plantations, pastures and native
vegetation. It is a serious pest in at least 16 countries,
including Hawaii, Fiji and Indonesia.
Potential to cause millions of dollars damage to primary
production, irreversible damage to sensitive habitats and
native plant communities.
HABITAT
Kosters curse prefers humid tropical lowlands and waterways,
ideally with an annual rainfall over 1,200mm, and grows in
both shaded areas and full sunlight.
Notifiable weed. Call Council for assistance.
33
KUDZU
Pueraria lobata
Class
3
Kudzu is a vine native to China, Japan, south-eastern Asia,
Malesia and some Pacific Islands.
A major pest in Japan and the United States, it has been
present in Queensland since around 1941. Presently there are
numerous small infestations scattered along the east coast of
Queensland and northeast NSW.
Kudzu is in the genus Pueraria, in the pea family Fabaceae,
subfamily Faboideae. They are climbing, coiling, and trailing
perennial vines that flower in summer. On supporting
vegetation they can grow to 18m high.
The plant produces tubers, stems with appressed to spreading
brown hairs, and stipules 0.8-1.6cm long. Leaflets are lobed or
not lobed, and the lower surface paler than the upper surface.
Seeds are 3.5-4mm long.
Kudzu mainly spreads vegetatively, which explains why it does
not spread rapidly. If however it was sold to be planted widely,
it has the potential to become a serious problem.
EFFECTS ON THE ENVIRONMENT Plants smother supporting vegetation and the dense canopy
excludes light from lower plants. Tubers are edible and Kudzu
was grown as a root crop in Asia where its common name is
Japanese arrowroot.
HABITAT
It is a major weed in south-central and south-eastern USA
where it was introduced as an ornamental, and at a later stage
promoted for pasture and soil conservation.
CONTROL METHOD
34
MICONIA
Miconia species
Class
1
Miconia, also known as Velvet tree, is native to South
America and can be found from Mexico to Brazil. Miconia was
introduced to Tahiti in 1937 and now grows on 70% of the
island, where it is described as the ‘green cancer’. In Hawaii it
is described as the ‘purple plague’.
It was introduced to Australia in1963 as a garden ornamental.
Naturalised populations are now known to occur in Far North
Queensland.
Seeds can remain viable for over five years, and though they
usually germinate in the sun, they can grow under a canopy.
Miconia grows as a small tree, up to 15m tall. Leaves are
commonly 60-70cm long, dark green with three prominent
veins on the upper surface, and distinctly purple-blue
undersides. Flowers are white to pink in colour and the 1cm
diameter fruit is dark purple.
EFFECTS ON THE ENVIRONMENT It is an unusually aggressive invader of moist habitats, and
a potentially devastating weed of Australian rainforests. It
has the ability to thrive in heavy shade and sunlight, and can
cause irreversible damage by forming dense thickets in the
understorey and completely replacing the native vegetation.
Half of Tahiti’s native plants are considered to be directly
endangered due to Miconia.
HABITAT
Miconia is a rainforest tree, and the climate throughout much
of northern and eastern Australia is ideal for the plant.
CONTROL METHOD
35
MIKANIA vine
Mikania micrantha
Class
1
Mikania is native to Central and South America, from Mexico
to Argentina and the Caribbean region.
It is a major weed of agriculture in the tropical areas of South
and Southeast Asia, including China and Malaysia.
In Australia the first infestations were discovered in Far North
Queensland in 1998 at Ingham and Bingil Bay near Tully.
Mikania is not known to be present in NSW.
It has a potential distribution that covers the coastal regions
of Northern Territory, northern Western Australia, Queensland
and Northern NSW.
Mikania is a rapidly-growing multi-stemmed vine that prefers
to climb over already established plants or structures.
EFFECTS ON THE ENVIRONMENT Mikania is a creeping or twining perennial vine capable of
growing to 20m high on supporting vegetation. It can smother
native vegetation, plantation crops, forests and infrastructure,
and is known as ‘mile-a-minute’ due to its rapid growth rate.
It is invasive under tree crops and in the understorey of
forests. It is able to grow up through the canopy of a forest.
Mikania produces toxins that, when released into the soil,
reduce the growth of other plants such as native vegetation,
crops and plantations.
HABITAT
Mikania thrives in open, sunny, disturbed areas, but will also
tolerate partial shade. It prefers warm and humid tropical
climates with rich damp soils and an annual rainfall over
1,000mm.
Notifiable weed. Call Council for assistance.
Photo: Navaneeth Krishnan
36
mysore thorn
Caesalpinia decapetala
Class
3
Mysore thorn is native to Japan, China, India and Malaysia.
It is present in many countries around the world and is an
invasive weed in New Zealand, the Dominican Republic,
South Africa and Hawaii.
In Northern NSW there are many localised infestations. Small,
localised infestations are also present along the central coast
of NSW.
Mysore thorn is a large evergreen shrub growing 2-4m high, or
up to 20m high when climbing over supporting vegetation.
It reproduces by seed, which may stay viable in the soil for up
to 10 years. The seed is mainly dispersed by animals that feed
on the fruit, such as rodents, birds and cattle. Seed pods float
on water, spreading seeds downstream to new locations.
The branches produce new roots when they come into contact
with the ground. Plants will re-shoot vigorously when cut.
Branches are covered by hooked thorns, and pale yellow
flowers are produced during winter and spring.
EFFECT ON THE ENVIRONMENT
Originally planted in gardens as a hedge plant, it is now an
environmental weed. It can affect the biodiversity of native
bushland areas by out-competing and smothering native
species.
HABITAT
Mysore thorn prefers humid coastal conditions in sub-tropical
to tropical climates. It will often grow in disturbed areas,
roadsides, pastures, creek banks, native grasslands and along
the edges of bushlands and forests.
CONTROL METHOD
37
Paper Mulberry
Broussonetia papyrifera
Class
2
A fast-growing, smooth bark, single-stemmed shrub or small
tree 15m tall. The twigs are hairy and reddish-brown. Bark
is tan and smooth to moderately furrowed with viable leaves
of 8-20cm. Male flowers are yellowish-white and arranged in
an elongate inflorescence (up to 8cm long). Female flowers
take the form of a round inflorescence in spring that forms
red to orange/yellow fruits (green when immature), 1-4cm in
diameter, in summer.
EFFECT ON THE ENVIRONMENT
Invades and eliminates native vegetation and disturbed areas
to form dense stands and dominate understorey vegetation.
Out-competes and replaces native grasses, ground covers
and shrubs. Shade tolerant. Spreads rapidly in well drained
soils with an annual rainfall over 1,000mm. When roots
or stems are damaged or cut, suckering occurs giving the
plant the ability to increase size and density. It also triggers
reactions in people who suffer allergies.
HABITAT
Has the potential to become a major environmental weed,
particularly in riparian areas, urban bushland, closed forests,
forestry plantations and forest margins in tropical, sub-tropical
and temperate areas. Grows in most circumstances, full
sun or heavy shade and thrives in disturbed or moist shady
sites. Bats and many introduced birds eat the fruit and may
disperse it into native ecosystems. Will also invade disturbed
areas especially industrial land, post-fire areas and transport
corridors (road and rail).
CONTROL METHOD
38
Parthenium weed
Class
1
Parthenium hysterophorus
* WEED OF NATIONAL SIGNIFICANCE *
Parthenium weed is annual, native to the Caribbean region. It
is thought to have been introduced to Australia from the USA
on machinery during World War II and as a contaminant of
imported pasture seed during the 1950s.
Although endemic to central Queensland and spreading
into southern Queensland, NSW continues to be free from
established populations of Parthenium weed. Outbreaks on
private property occur in NSW but are not common.
The upper half of the main stem becomes highly branched at
flowering, producing creamy-white flowers at the tips of the
stems. The deeply-lobed leaves are alternately branched on
the stems, pale green and covered with soft, fine hair.
Prior to late-flowering, the plant can be easily mistaken
for Bishops weed (Ammi majus) and Hemlock (Conium
maculatum). After it has set seed and becomes woody it can
then be mistaken for Fleabane (Conyza spp.).
EFFECTS ON THE ENVIRONMENT
The weed adversely affects human and animal health and can
cause respiratory problems, severe dermatitis, tainted meat
and tainted milk. Never touch the plant with bare hands as
severe allergic reactions can occur.
HABITAT
Conditions for the growth of Parthenium weed are ideal in
most areas of NSW, with the exception of very arid or wet
areas. Once established, plants will survive both droughts and
frosts.
Notifiable weed. Call Council for assistance.
Photo: Phil Blackmore
39
pond apple
Amnona glabra
Class
1
* WEED OF NATIONAL SIGNIFICANCE *
Pond apple is a native of North, Central and South America
and West Africa and thrives in areas that are moist and sunlit.
Pond apple can be confused with native mangroves as
superficially they look similar and are often found growing
together. Pond apple plants are usually single-stemmed with
grey bark. When seedlings germinate together, they can form
multiple-stemmed plants that can fuse together and appear
single-stemmed.
EFFECTS ON THE ENVIRONMENT
Pond apple is a very hardy, semi-deciduous woody tree that
can form extremely dense thickets, maturing into dark forests.
This aggressive invader usually grows to a height of 3-6m, but
can grow as tall as 15m.
It was introduced to Australia as a salt- and water-tolerant
grafting stock for the closely related, commercially produced,
Custard apple (Annona reticulata). It is still used as a
rootstock for Custard apple in Northern Queensland.
Pond apple is regarded as one of the worst weeds in Australia
because of its invasiveness, potential for spread, and
economic and environmental impacts.
HABITAT
Pond apple can grow in the same environments as native
mangroves due to its ability to tolerate flooded areas and salt
water. It is found in a wide range of disturbed and undisturbed
wetlands and rainforests, including streams, riverbanks,
wetlands, sedgelands, mangrove communities and high tide
zones on beaches.
Notifiable weed. Call Council for assistance.
40
SENEGAL TEA PLANT
Gymnocoronis Spilanthoides
Class
1
Senegal tea plant has stems that are ribbed, pale green and
erect, becoming prostrate with age. Hollow between the nodes
and buoyant, able to form tangled floating mats. Stems branch
at nodes and are 1-1.5m long and 5-20mm diameter. Fine,
fibrous roots form at stem nodes. White, pom-pom-like flowers
1.5-2cm diameter occur in groups at ends of stems. Flowering
starts in late spring/early summer and continues until
temperatures fall. Flowers have a strong fragrance. Seeds are
yellow-brown, 5mm diameter and ribbed. Reproduces by plant
fragments and seed; fragments develop roots and new stems
when they come into contact with soil. Seeds can be moved
in faster flowing water or in mud on vehicles or animals. Plant
fragments move in flowing water/flood waters.
EFFECT ON THE ENVIRONMENT
An extremely hardy plant with a growth rate exceeding 15cm
a week in fertile situations. Long branching stems produce a
tangled web of vegetative material that, growing out from the
bank, quickly covers the water surface. It impedes water flow,
navigation and recreation.
HABITAT
Senegal tea prefers tropical, sub-tropical and warm‑temperate
regions, and will grow in damp floodplain soils, on the margins
of creeks/dams, in wetlands and in still/slow-flowing fresh
water. Plants can grow when fully submerged, but growth is
slower and plants are smaller. In some infestations plants
have been found growing on the floodplain up to 150m from
the water body.
Notifiable weed. Call Council for assistance.
41
siam weed
Chromolaena odorata
Class
1
Siam weed is recognised as one of the world’s worst tropical
weeds. It is a native of Central America and was first identified in
Australia in 1994, with infestations along the Tully River and near
Mission Beach, in North Queensland.
It was first reported in Africa in the 1940s. Today it is a major weed
in Nigeria, Ghana, Cameroon, Zaire and South Africa.
Siam weed is considered one of the world’s worst tropical weeds
due to its quick invasion and establishment. It invades and outcompetes pastures, crops and native vegetation.
It is known to grow up to 20m high as a climbing plant. Its leaves
are almost triangular. White to pale-lilac flowers occur in flattopped clusters during winter. They also contain fine barbs, which
means they readily stick to clothing, equipment and animals.
EFFECT ON THE ENVIRONMENT
Siam weed is on the Alert List for Environmental Weeds, a list
of 28 non-native plants that threaten biodiversity and cause
other environmental damage. It has the potential to seriously
degrade Australia’s ecosystems.
The plant is toxic to livestock, killing more than 3,000 cattle
annually in the Philippines. The toxin also causes abortions in
cattle and is suspected of being a fish poison.
It can also cause allergic reactions.
HABITAT
Siam weed is now a serious weed in Mauritius, India, Sri
Lanka, south-east Asia, China, the Philippines and Guam.
Notifiable weed. Contact Council for assistance.
Photo: J Bocking
42
Photo: J Bocking
Tropical soda apple
Solanum viarum
Class
1
An upright, branching, perennial shrub growing up to 2m.
Broad-based, straight, cream-coloured prickles to 12mm long
scattered on most plant parts. Leaves 10-20cm long, 6-15cm
wide, densely covered in short hairs; mid-veins and primary
lateral-veins cream-coloured. Flowers white with five petals
2-4mm long in clusters of three to six, developing into yellow
golf‑ball-size fruit containing up to 45,000 seeds.
EFFECT ON THE ENVIRONMENT
Invades and eliminates native vegetation and disturbed areas;
forms dense stands, dominating understorey vegetation. Outcompetes and replaces native grasses, ground covers and
shrubs. Shade tolerant. Spreads rapidly on waterlogged or
poorly drained soils but will grow on drier land in higher rainfall
areas. Foliage unpalatable to livestock (reducing carrying
capacities). Prickles restrict grazing by native animals and
livestock; thickets can prevent animals’ access to shade and
water. A host for many diseases and pests of cultivated crops.
Contains solasodine (poisonous to humans).
HABITAT
Has the potential to become a major environmental weed,
particularly in damp coastal areas, along banks of waterways,
mangroves, open forests and moist gullies. Grows in most
circumstances, full sun or shade, moist or dry conditions.
Thrives in disturbed or moist shady sites in riparian areas;
potential to spread in coastal regions of NSW and Queensland
and inland through cattle movements. Seed can be spread
by feral animals and birds feeding on fruit; and via water and
contaminated produce, soil and equipment.
Notifiable weed. Contact Council for assistance.
43
water lettuce
Pistia stratiotes
Class
1
Water lettuce is native to Asia, Africa and equatorial America.
There is debate about whether the Northern Territory, where
it was collected in 1946, forms part of its native range. It has
since spread to Queensland, NSW and Western Australia.
Water lettuce is a free-floating plant that looks like an open
head of lettuce. Pale green leaves are ribbed, wedge-shaped
and form a rosette. They are spongy to touch and have a
velvety appearance due to the small thick hairs that cover
them.
Water lettuce is a perennial plant that reproduces vegetatively
and from seed. Pieces can be spread by boats or fishing
equipment moving it from an infested to a clean water body.
EFFECT ON THE ENVIRONMENT
Under favourable conditions, Water lettuce will produce
abundant growth, expand rapidly and form obstructive mats.
These large, dense floating mats can have negative impacts
on native aquatic plants and animals. They can also interfere
with irrigation, boating and water sport activities.
Thick mats of Water lettuce are also known to harbour
disease-causing mosquitoes.
HABITAT
It is thought to have been introduced into NSW rivers and
dams via eel traps from Queensland, and as an aquarium
plant and water garden specimen sold in nurseries. Rivers,
wetlands, lakes, reservoirs and slow-moving streams are most
at risk from this weed, especially in the subtropical parts of the
state.
Notifiable weed. Contact Council for assistance.
44
white blackberry /
mysore raspberry
Class
3
Rubus niveus
Also known as White blackberry or Hill raspberry, Mysore
raspberry is originally from India and South-East Asia.
It forms dense, impenetrable thickets and has become
invasive in some areas where it has been introduced,
including Hawaii and the Galapagos Islands.
Mysore raspberry is a large scrambling shrub, 3-4.5m high,
with sharp, hooked thorns.
Its leaves are hairy and made up of from 5-9 leaflets, 2.5-6cm
long, with toothed edges. The upper side is dark green while
the underside is white. Pink or mauve flowers, 10-15mm in
diameter, occur in dense clusters. Typical raspberry fruit, 1015mm in diameter, change from red to purple-black as they
ripen.
They are spread by birds, rodents and other animals. They
contain very large numbers of seeds, which can remain viable
for up to two years. Very dense seed banks can accumulate in
the soil.
EFFECT ON THE ENVIRONMENT
Mysore raspberry can form dense thickets that displace native
plants and prevent them from regenerating. It can also invade
farmland.
HABITAT
Mysore raspberry has become invasive in moist forest
areas in other countries. It tolerates a wide range of climatic
conditions.
CONTROL METHOD
Photo: Forest & Kim Starr
45
witchweed
Striga species
except native sp. and Striga parviflora
Class
1
Witchweeds are parasitic herbs that grow on the roots of host
plants. All Striga species, except for the native Striga parviflora,
are Prohibited Weeds in NSW.
Witchweeds are native to tropical Africa, India, the Middle East
and China. They infest an estimated two-thirds of all cropping
in Africa.
In July 2013, Striga asiatica was found on a small number of
properties near Mackay in Queensland. Witchweeds are not
known to occur in NSW.
Witchweeds are dependent on a host plant, only germinating
when exposed to certain chemicals that host plants exude.
Seeds are spread short distances by wind, and further by water
and soil attached to animals, machinery, tools, footwear and
clothing. Contaminated crop seed is the most likely way for
Witchweeds to be introduced into an area.
The presence of Witchweed may be indicated by symptoms
in the host plant, which are similar to severe drought stress,
nutrient deficiency and vascular disease.
EFFECT ON THE ENVIRONMENT
Worldwide, at least 11 species of Witchweed are known to
attack crops. They are serious weeds of maize, millet, rice,
sugarcane, sorghum and legume crops. Crop losses can be as
high as 100%. Parasitic weeds like Witchweed are among the
most destructive and difficult-to-control weeds in agriculture.
HABITAT
Witchweed prefers intensive agriculture where frequent crops,
monocultures and fertilisers encourage growth and seed
production.
Notifiable weed. Contact Council for assistance.
Photo: Qld government
46
Photo: Bart Wursten
yellow bells
Tecoma stans
Class
3
Yellow bells is a native of tropical America. It is widely cultivated
as an ornamental plant in subtropical and tropical areas of the
world.
It was introduced into Australia as an ornamental plant and was
first recorded as naturalised in 1973 near Roma in Queensland.
It has also become naturalised in southern Asia, Argentina,
Brazil, South Africa and some oceanic islands.
Isolated infestations occur in coastal and floodplain areas on
the NSW North Coast.
Yellow bells primarily reproduces from seed. These are
primarily wind-borne, but are also spread by water and
dumping garden waste.
It is a large shrub or much-branched small tree 3-8m tall, rarely
to 10m tall. Flowers are bright yellow, seeds are paper, winged
and to about 2.2cm long.
EFFECT ON THE ENVIRONMENT
Yellow bells invades riparian areas, edges of rainforest and
eucalypt forest, open woodlands, grasslands, waste areas, sand
dunes, agricultural land and other disturbed areas.
Although palatable to stock, it reduces feed quality, restricts
access for stock and machinery and competes with orchard
plantings. It has the potential to be a serious weed of much of
tropical and subtropical Australia.
HABITAT
It is grows in riparian areas, edges of rainforest and eucalypt
forest, open woodlands, grasslands, waste areas, sand dunes,
agricultural land and other disturbed areas.
CONTROL METHOD
47
HOW YOU CAN HELP
How you CAN help
•
Visit the Rous County Council website
(www.rous.nsw.gov.au - then select Weed biosecurity
- weed information - noxious-weeds) for a list of local
noxious weeds.
•
Visit the NSW Department of Primary Industries
website (www.dpi.nsw.gov.au/agriculture/pests-weeds/
weeds) for more information and the most current
noxious weed declarations for the council area.
•
When planting in your garden use local native species
or non-invasive species.
•
Do not throw garden waste into bushland. Use
compost bins or council’s greenwaste bins.
•
Control noxious and environmental weeds in
accordance with required control measures.
oTHER RESOURCES
Local Land Services
Weeds Australia
The Weed Society of NSW
Council of Australian Weed Societies (CAWS)
Noxious Weeds Act 1993
Botanic Gardens Trust
48
Identify a weed
For assistance in identifying weeds in the Council area,
please contact Rous County Council on 6623 3847.
Above: Alligator weed, Eltham swamp.
Thank you to Sutherland Shire Council for their assistance in producing
this booklet.
Control methods and symbols shown throughout this section courtesy
of Sydney Weeds (sydneyweeds.org.au).
49
OUR CONTACT DETAILS
Hymenachne seed heads.
Rous County Council - Weed biosecurity
Level 4, 218-232 Molesworth Street, Lismore NSW 2480
PO Box 230, Lismore NSW 2480
T: (02) 6623 3800 F: (02) 6622 1181
[email protected] www.rous.nsw.gov.au