Prescribed measures for the control of noxious weeds

Descriptions of management measures that are 'Prescribed' under the Catchment and Land Protection (CaLP) Act 1994 and Regulations 2002.

These are the prescribed measures to comply with a Notice served under the CaLP Act:

• application of a registered herbicide
• cultivation
• physical removal
• mulching

Notice under CaLP Act

Where a land owner is served with a Notice under the CaLP Act for the eradication or control of noxious weeds, one or more of the prescribed measures described in that Notice must be undertaken in order to comply with that Notice. It is strongly recommended that these prescribed measures are also used when undertaking any noxious weed control as they have been determined to be the most effective control measures for a given species.

Application of a registered herbicide

Under Victorian legislation, there are controls on the use of agricultural chemicals which include requirements for keeping records of chemical applications. It is the responsibility of the user to be familiar with this legislation.

Farm chemicals are registered for specific uses. Each chemical has a 'product label', which documents the approved use, and the approved rate of use, within each State.

The product label is important in determining the appropriateness of chemical use and must be followed at all times.

Other controls include the requirement to possess an Agricultural Chemical User Permit (ACUP) to allow use of certain chemical products and restrictions of use of certain chemical products in agricultural chemical control areas.

Choose only products registered for use in your particular situation. Read the product label carefully and follow all label instructions.

Chemical retailers can provide information on chemical products registered for your situation.

They can also supply a 'material safety data sheet (MSDS)' which outlines the health and safety information about a product. This information is also available from chemical manufacturers and product labels are available from Australian Pesticides and Veterinary Medicines Authority.

Spraying

Spraying can be effective on both large and small infestations. The larger the infestation or plants, the more chemical you will need.

Before spraying, consider the weather conditions and proximity to:

• native vegetation
• vineyards
• organically grown crops
• waterways
• other sensitive areas

Treat the plants when they are actively growing and avoid spraying when they are under stress so that you maximise the opportunity for the plants to take up the chemical.

Often more than one spray application will be needed to kill all the plants in a large infestation. Plants must be completely covered with herbicide, as parts that are missed may continue to grow.

Always read and adhere to the directions provided on the product label.

In most situations the sprayed plant should not be removed for at least 6 months after spraying to allow the herbicide time to work. Refer to the product label for directions.

Be aware that dead plants may increase fire hazard.

Before starting herbicide treatment in a new area, all areas treated the previous year should be checked and re-sprayed if necessary.

Incorporation of a compatible marker dye in the herbicide will assist in identifying treated areas areas and ensure that all plant surfaces are covered. Incorporation of a compatible marker dye may be a legal requirement for complying with a Directions Notice or Land Management Notice.

Protective clothing including gloves and face shield should be worn when working with any herbicide.

Cutting and painting

This method is used mainly for trees and woody weeds. Stems should be cut as low as possible and the stumps immediately painted with a registered herbicide. If the herbicide is not applied immediately after cutting, the stump seals up and the herbicide will not be fully absorbed, allowing regrowth to occur. Refer to the product label for directions. This method is usually only suitable for small infestations and large isolated plants.

This method is usually only suitable for small infestations and large isolated plants.

Compared with spraying, the cutting and painting method involves a more selective application of herbicide with reduced volumes.

Protective clothing including gloves and face shield should be worn when cutting and painting plants by hand.

Cultivation

Cultivation means turning the soil to a depth of at least 15 centimetres with tools such as disc ploughs, harrows and deep rippers. Cultivation can be useful for treatment of seedlings and regrowth.

The best time to cultivate is before the seed sets. Cultivation is not a suitable control method for plants which spread vegetatively as small pieces of such plants can usually regenerate.

Cultivation can increase the likelihood of germination of seeds that would otherwise be dormant in the soil. Cultivation is only recommended as an addition to other control methods. Frequent cultivation will also contribute to soil erosion and breakdown of the soil structure in many soils.

If any control is to be undertaken which may result in any disturbance of native vegetation, culturally significant areas or waterways, you should contact Agriculture Victoria.

Physical removal

Physical removal aims to remove the entire plant, including its roots, from the soil, therefore reducing the above-ground plant-mass before follow up methods are applied.

This can be achieved by 'grubbing' out by hand or, if the plant is large enough, removal by machinery, (tractor and chain, bobcat, or excavator fitted with a grab bucket).

All root systems should be removed, as some plants will re-shoot from roots left in the ground.

Removal by hand is only suitable for machinery hygiene.