Injurious weeds

What is an injurious weed?

An injurious weed is a plant species listed in the Weeds Act. The species listed are plants that can produce copious amounts of seed that can spread easily and can affect the quality and quantity of agricultural crops.

Taken from the Weeds Act 1957

Injurious weeds can be controlled using a number of chemical and cultural means. Care should be taken to choose the most appropriate method for each site. This applies particularly to sites of special conservation interest where control of the injurious weeds may risk damaging rare or valuable flora and fauna. In these situations expert advice should be sought before any action is taken.

Injurious weed control using herbicides

Instructions for use including operator and environmental protection, the crops or plants on which the product may be used, maximum dose, harvest interval and other details are shown on the product label. Each time a product is used you must read the label and follow the instructions.

Some products are only available to operators who hold a certificate of competence.

Non selective herbicide treatment

Control of injurious weeds can be undertaken using a non-specific herbicide such as glyphosate either as an overall spray or using a height selective applicator or spot treatment.

Selective herbicide treatment

Injurious weeds can be controlled using selective herbicides. Although most products are generally used as an overall spray, some can also be applied through a selective height applicator or as a spot treatment to improve their selectivity.

The following shows the most favoured active ingredients for the control of each injurious weed specified under the Weeds Act 1957. These active ingredients may be available alone or in mixtures with other chemicals and qualified advice should be obtained to determine the most appropriate product especially when mixed populations of weeds occur.