Introduction

In any area, there are certain pest plant species that are 'proclaimed' under the Natural Resources Management Act 2004.
 

Generally, pest plants are proclaimed because they are poisonous to livestock, or are particularly difficult to control and have a high potential to spread and reduce the value of land.
 

The actual species of plants that are declared pest plants varies in different parts of the State, and interstate. Examples of declared weeds in the Mt Lofty Ranges include gorse and blackberries. Statewide, these include golden dodder, poison ivy, perennial thistle and Rhus.
 

All landowners have specific responsibilities to control proclaimed weeds on their properties, and to report any of these to the relevant Natural Resources Management Board in their area.
 

Currently, adjoining landowners are responsible for controlling pest plants on roadsides; otherwise Natural Resources Management Boards will undertake such control with adjoining landowners liable for the costs.
 

Where possible, a range of methods should be used to control weeds (e.g. good weed hygiene on the property, good grazing management, re-seeding pastures) rather than just a single method (such as relying on chemicals). An integrated weed control program is an important aspect of property management, and is one of the components of a property management plan.
 

Steps to achieve best practice

Suggested steps to identify and control declared weeds on the property are as follows. Control of declared pest plants should be a high priority.
 

 
Step 1

Regularly inspect the property for weeds, and identify any declared pest plants that are present. You can get assistance and advice on weed identification and control from rural consultants and advisers, and from your Natural Resources Management Board (replacing Animal and Plant Control Boards).
 

If you find any declared pest plants on the property, notify your Natural Resources Management Board.
 

 
Step 2

Carry out weed control programs for any problem weeds, using methods that are recommended for your area (especially proclaimed weeds) by your Natural Resources Management Board. Consider using selective weed sprays in pastures (if required).
 

 
Step 3

Ensure there is good weed hygiene on the property (see Preventing weeds entering or leaving the property).

• Ensure as far as possible that any hay or feed brought on to the property is free of weeds.
• Quarantine new horses for 10 - 14 days to prevent seed spread on to the property.
• Clean boots, vehicle tyres etc before leaving properties visited for horse events.
• Designate a carpark area for visitors and entry/exit point for the property for contractors and visitors.
• Speak to contractors about your concerns and provide a cleaning down area for machinery if this is determined necessary.
• Put up signs or use other means to communicate your weed quarantine precautions to visitors.

 
Step 4

Manage pastures well (see Pasture composition). Good quality pastures that have mostly desirable pasture plants will tend to out-compete most weeds including pest plants.

• Maintain good soil fertility and ensure soil pH does not become too acid. Do regular soil tests for fertility and pH, and apply fertiliser and/or lime according to soil test results.
• Consider renovating or re-seeding pastures if the amount of desirable pasture plants is low.
• Where possible, use rotational grazing of pastures (see Maintain groundcover), and don't overgraze pastures because this makes it easy for weeds to proliferate.

 
Step 5

Each year, review your weed control program. Each season, monitor any declared pest plants present in pasture paddocks. Look at how successful or otherwise your weed control has been, and modify the program accordingly.
 

You can get help from your Natural Resources Management Board to accomplish this task.
 

Links

• Natural Resources Management Boards/Animal and Plant Control Boards including fact sheets e.g. www.mlrapcb.net
• Legislation: www.dwlbc.sa.gov.au/legislation.html or www.parliament.sa.gov.au
• Chemical Users Project: Adelaide and Mount Lofty Ranges Natural Resources Management Board / Torrens Catchment Water Management Board Ph. 8271 9190.
• Land Management Program advisers based in the Mt Lofty Ranges: www.amlrnrm.sa.gov.au/services.html
• Weed management guide - weeds of national significance - Fact Sheet series, CRC for Australian Weed Management.
• Weeds of national significance: www.weeds.org.au/natsig.htm
• A Legal guide for South Australian primary producers - SA Law Society, available from PIRSA offices, Natural Resource Centres (but note some legislation referred to is now superseded)