WeedsThe following information has been taken directly from the NSW Department of Primary Industries web site.

Weed classificationsWeeds are often classed in broad groups

depending on their characteristics and impacts.  The main groups of weeds are:◦ Noxious weeds ◦ Environmental weeds ◦ Agricultural weeds ◦ Weeds of National Significance (WONS) and ◦ National Environmental Alert List Weeds.

Many weeds can be classified in more than one of these groups.  For example, blackberry can be classed as a noxious weed, environmental weed and agricultural weed, depending on its situation and is also listed as one of Australia’s Weeds of National Significance (WONS).

Noxious Weeds Some serious weeds are required by law to be controlled by all

landholders in an area. These are known as noxious weeds and the law that controls these in NSW is the Noxious Weeds Act 1993.

Weeds that are declared noxious are those weeds that have potential to cause harm to the community and individuals, can be controlled by reasonable means and most importantly, have the potential to spread within an area and to other areas.

A weed is declared noxious because its control will provide a benefit to the community over and above the cost of implementing control programs.

Many ‘bad’ weeds do not meet the criteria for declaration.  Noxious weeds will have limited distribution with the potential to become more widespread and will cause impact on agriculture, human health or the environment.

In New South Wales the administration of noxious weed control is the responsibility of the Minister for Primary Industries under the Noxious Weeds Act 1993. The Act is implemented and enforced by the Local Control Authority (LCA) for the area, usually local government.

The Act imposes obligations on occupiers of land to control noxious weeds declared for their area. 

There are five classes of noxious weeds identified in the Act (see Table 1).  All Noxious Weeds in NSW are listed in the Noxious Weeds database

Control class Weed type Example control requirements

Class 1

Plants that pose a potentially serious threat to primary production or the environment and are not present in the State or are present only to a limited extent.

The plant must be eradicated from the land and the land must be kept free of the plant.

The weeds are also "notifiable" and a range of restrictions on their sale and movement exist. 

Class 2

Plants that pose a potentially serious threat to primary production or the environment of a region to which the order applies and are not present in the region or are present only to a limited extent.

The plant must be eradicated from the land and the land must be kept free of the plant.

The weeds are also "notifiable" and a range of restrictions on their sale and movement exist.

Class 3

Plants that pose a potentially serious threat to primary production or the environment of a region to which the order applies, are not widely distributed in the area and are likely to spread in the area or to another area.

The plant must be fully and continuously suppressed and destroyed.*

Class 4

Plants that pose a potentially serious threat to primary production, the environment or human health, are widely distributed in an area to which the order applies and are likely to spread in the area or to another area.

The growth and spread of the plant must be controlled according to the measures specified in a management plan published by the local control authority.*

Class 5

Plants that are likely, by their sale or the sale of their seeds or movement within the State or an area of the State, to spread in the State or outside the State.

There are no requirements to control existing plants of Class 5 weeds.

However, the weeds are "notifiable" and a range of restrictions on their sale and movement exists.

NOTE: All Class 1, 2 and 5 weeds are prohibited from sale in NSW.* In some cases the following wording has also been inserted "the plant may not be sold, propagated or knowingly distributed."

Table 1 Control classes of noxious weeds

Environmental weeds

Environmental weeds are plants that represent a threat to the conservation values of natural ecosystems.  They invade native plant communities and out-compete them causing a reduction in plant diversity and resulting in a loss of habitat for native animals.

Some examples of environmental weeds are bridal creeper, bitou bush, boneseed, blackberry and lantana.

Environmental weeds can also be native Australian plants that are not local (indigenous) to the area they are growing in.  They have the potential to displace and out-compete plants within the local plant community.  Examples of native Australian plants that are doing this are sweet pittosporum and coast wattle.

Agricultural weeds

Agricultural weeds are plants that represent a threat to agricultural production.  They reduce the area available for agricultural activities, interfere with agricultural practices and affect the quality of produce.

Some examples of agricultural weeds are serrated tussock, thistles, blue heliotrope, St John’s wort, Paterson’s curse and blackberry.

Weeds of National Significance

Under the National Weeds Strategy, 20 introduced plants were identified as Weeds of National Significance (WONS).

These weeds are regarded as the worst weeds in Australia because of their invasiveness, potential for spread, and economic and environmental impacts.

The weeds are:

◦Alligator Weed ◦Athel pine ◦Bitou bush /

Boneseed ◦Blackberry ◦Bridal creeper ◦Cabomba ◦Chilean needle grass ◦Gorse ◦Hymenachne ◦Lantana

◦Mesquite ◦Mimosa ◦Parkinsonia ◦Parthenium weed ◦Pond apple ◦Prickly acacia ◦Rubber vine ◦Salvinia ◦Serrated tussock ◦Willow

More information: Weeds of National Significance (www.environment.gov.au)

National Environmental Alert List Weeds

Under the National Weeds Strategy, 28 environmental weeds were identified National Environmental Alert Weeds.  Alert Weeds are non-native plant species that are in the early stages of establishment and have the potential to become a significant threat to biodiversity if they are not managed.

The weeds are:Ballerina Blue hound's tongue Cane needle grass Chinese rain tree Chinese violet Cutch tree Cyperus False yellowhead Garden geranium Heather Holly leaved senecio Horsetail species Karroo thorn Kochia

LagarosiphonLaurel clock vine Leaf cactus Lobed needle grass Orange hawkweed Praxelis Rosewood Senegal tea plant Siam weed Subterranean cape

sedge Uruguayan rice grass White Spanish broom White weeping broom Yellow soldier

The following are weeds that we have, or have had

at the school farm.

Paterson’s Curse

Saffron thistle

Scotch thistle

Marshmallow weed

African box thorn

Stinging nettles

Variegated thistle

Prickly lettuce

The following weeds are other significant weeds in

Australia.

Blackberries

Parthenium weed

Lantana

IPM (Integrated Pest Management)

IPM is the use of a range of different tools, equipment and technology to suppress or eradicated targeted pests.

It can be further broken down to IWM (Integrated Weed Management) which is targeted specifically at weeds.

A weed is any plant that is unwanted.In some situations a plant may be of

benefit, for example: paspalum as a grazing plant. But in a wheat crop it is a weed.

IPMIPM is broken in

to several groups. They are:◦ Cultural control◦ Mechanical

control◦ Physical control◦ Biological control◦ Chemical control

Cultural controlCultural or management control takes in

to account a number of factors which can influence the establishment and spread of weeds. Here are some examples:

Using tolerant cultivars in crops.Crop rotation to break the weed cycle.Time of planting.Fertilisers and time of fertilising.Sanitation, keeping tractors and

machinery clean and free off weed seeds.

Cultural controlThis could include

planting competition plants which are beneficial.

Applying appropriate sowing rates and row spacings.

Grazing land only back to a certain level to allow recovery of wanted plants.

Crop rotation.

Mechanical control

This is using machinery or equipment to disturb the root zone of the weeds.

For example: ploughing a paddock before sowing.

Mechanical controlThese can also

include:◦ hoeing and

chipping◦ Slashing and

cutting◦ Chaining or

scrubbing

Biological controlThis is using one

living organism to control another.

An example of this is using Lady beetles to kill aphids.

Another less successful example is using cane toads to kill the cane beetle.

Biological control

Chemical controlThis is the use of

agricultural chemicals to kill targeted weeds.

This is a common method of control. However due to the nature of chemicals, this should be the last option.

Physical controlThis is using

manual labour to control weeds.

Examples of this may be:◦ Pulling weeds out

by hand◦ Drainage ◦ Temperature◦ Light

SafetyLike all aspects of agriculture it is

important to consider any safety implications.

Identify the hazards which may arise and use appropriate measures to eliminate or reduce the hazard.

Reminder:◦The hierachy of risk control

Eliminate Substitute Isolate Mechanical Administrative PPE

PPE (Personal Protective Equipment)Here is a sample of the PPE

which may be used.