Slashing and mowing

Slashing and mowing is used for removing large areas of unwanted herbs and grasses that are not currently seeding.

Before you start slashing or mowing, make sure:

  • you have the right safety equipment
  • the weather conditions are good, that is, a sunny day
  • all pets and children are safely away from the treatment area
  • you have read and heeded all of the herbicide labels and equipment manuals
  • you do not slash or mow if the plants are wet as seeds will stick to you and your equipment which can lead to further spread
  • all equipment is maintained and functional


The equipment you will need is:

  • hat, safety eyewear, long-sleeved shirt, long pants, covered footwear
  • face shield, garden gloves, ear protection and shin guards
  • mower, whipper snipper or brush cutter

Now you are ready to start slashing and mowing your weeds.

For large areas tractor slashers are most appropriate while a mower or whipper snipper may be suitable for small to medium areas. Whipper snippers are usually used in conjunction with both machines to manage areas not accessible to the larger machines, for example along fence lines.


It is crucial to the success of this treatment method that the plants are slashed before they begin producing flowers, fruits or seeds.

Slash or mow as low as possible to retard the plant's growth. Slashing is effective for annual species (plants that germinate, seed and die within 12 months).

For perennials (plants that germinate and seed through many years), slashing or mowing before seed production will prevent further seed entering the soil seed bank.

Continual slashing or mowing will result in a gradual decline in weed seed population in the soil.

Some perennial weed species will persist via the perennial root stock for many years and may need to be overall sprayed.

Clean up

All equipment should be cleaned away from stormwater drains and at least 50 metres away from water courses.

Try to use the same area every time you clean equipment. This will help you to identify and treat weeds that appear. Target the hard-to reach areas with a hose or a brush.

More information

For more information send an email to the Invasive species team.