Invasive plant control options

Invasive succulents can reduce grazing land and displace native vegetation. Invasive cactuses can also injure wildlife and hinder livestock movement. Follow up monitoring and control are essential for the success of any of the below control methods.

Manual removal

Invasive succulents and cacti can reduce grazing land, poison stock, and displace native vegetation. Invasive cacti can injure wildlife and hinder livestock movement.

Follow up monitoring and control are essential for the success of any of the below control methods.

Smothering

Solarisation and the use of weed matting can be effective where you do not wish to use herbicides. It involves putting down thick plastic to inhibit photosynthesis or weed matting to smother the weeds. It usually takes up to a year to kill the plants however the time will vary according to weather conditions. Follow up control and revegetation are essential.

Stem injection

This involves injecting the cacti with herbicide so that it is transported throughout the plant and eventually kills it.

Foliar spray

Involves spraying herbicide onto the plant which is then absorbed into the plant. Foliar spray can be applied by a back pack sprayer for smaller areas or a quickspray unit for large scale weed control. Sunshine Coast council has back pack kits and quick spray units for hire.

Useful resources to help you get started

Invasive succulents and cacti in south east QLD: Identify a weed.

• How to control wheel cactus (YouTube video | Northern and York Landscape Board)
• Opuntioid cacti management guide (Department of Primary Industries and Regional Development)
• Opuntioid cacti identification guide (PDF, 3.3MB - agric.wa.gov.au)

Ground covers include low growing plants that spread along the ground and tend to smother and prevent regrowth of other plants. Follow up monitoring and control are essential for the success of any of the below control methods.

Smothering

Solarisation and the use of weed matting can be effective where you do not wish to use herbicides. It involves putting down thick plastic to inhibit photosynthesis or weed matting to smother the weeds. It usually takes several months to a year to kill the plants however the time will vary according to weather conditions. Follow up control and revegetation are essential.  

Hand held wick wiping

Wick wiping involves the application of herbicide by a hand held wick onto undesirable plants. Council has hand held wick wipers for hire.

Foliar spray

Involves spraying herbicide onto the leaves of the plant. Foliar spray can be applied by a back pack sprayer for smaller areas or a quickspray unit for large scale weed control. Sunshine Coast Council has back pack kits and quick spray units for hire.

Useful resources to help you get started

• Weedy groundcovers, herbs and grasses in South east Qld: groundcovers and grasses.
• Weed-Control-Methods (Land for Wildlife SEQ)
• Basic-Weed-control-techniques (NSW Gov)
• Dealing with Asparagus Fern in your garden (YouTube | Midcoast Council)
• Bush Regeneration Weed Control Techniques: Wick Wiping (YouTube | Coffs Harbour Regional Council)
• Using trees to control weeds- passive revegetation (YouTube | QLD Agriculture)

Pasture weeds are plants that are unpalatable, poisonous to stock or invasive in a farm. Pastures can be impacted by a range of invasive plants including grasses, broadleaf and woody weeds. Follow up monitoring and control are essential for the success of any of the below control methods.

Mowing, brush-cutting and slashing

Useful for preventing flowering and seed dispersal. This method is not useful for plants that spread by stem fragments or those that flower and seed at different times throughout the year. Mowing these types of plants will spread stem fragments and seeds to other areas. This method can be useful for groundsel bush if done annually prior to flowering. Timing is crucial for using this method for weed control.

Foliar spray

Involves spraying herbicide onto the leaves of the plant. Foliar spray can be applied by a back pack sprayer for spot spraying or a quickspray unit for large scale weed control. Sunshine Coast council has back pack kits and quick spray units for hire.

Wick wiping

Wick wiping involves the application of herbicide by either a hand held or a rotating wick on a trailer, onto undesirable plants. The use of a trailer wick wiper is only appropriate for faster growing pasture weeds where a distance is able to be achieved between the invasive plants and desirable pasture species so that the wick only touches the invasive plants. Council has both trailer and hand held wick wipers available for hire.

Useful resources to help you get started

• Invasive plants - Giant rat's tail grass (YouTube | Sunshine Coast Council)
• Giant Rats Tail grass fundamentals and insights for management (YouTube | Biosecurity QLD)
• Invasive Plant Management – Fireweed (YouTube | Sunshine Coast Council)
• Tropical Soda Apple: Identification and Control (YouTube | Coffs Harbour Regional Landcare)
• Bush Regeneration Weed Control Techniques: Wick Wiping (YouTube | Coffs Harbour Regional Landcare)

Invasive vines smother native vegetation and can even kill large trees. Most invasive vines can be cut at the base and either dug out or treated with herbicide. Two exceptions are the Air potato and Madeira vine which produces aerial tubers. This means you will need to treat the whole plant or remove and dispose of the whole plant. Follow up monitoring and control are essential for the success of any of the below control methods.

Cut and paint

Involves cutting the plant at the base with secateurs, loppers, a handsaw or chainsaw (depending on the size of the plant) and applying herbicide to the stump within 15 seconds (any longer than 15 seconds will affect results) to ensure that it is absorbed by the plant.

Scrape and paint

Involves scraping off a section of the outer bark and applying herbicide within 15 seconds (any longer than 15 seconds will affect results). Wrapping plastic around the area where the herbicide has been applied can assist with the absorption of the chemical by the plant. The herbicide is transported throughout the plants vascular system killing it entirely. This method is useful for Madeira vine and aerial yam as it can easily regrow from stem fragments and aerial tubers and therefore it is important to kill the whole plant.

Stem injection

Large vines can be stem injected. This involved drilling or cutting holes just beneath the bark to the sap wood of the plant around the stem 5cm apart and filling them with herbicide. The herbicide is transported throughout the plant and eventually kills it.

Useful resources to help you get started

• Weedy vines in South east Queensland Identify a Weed
• Invasive plants - Invasive vines (YouTube | Sunshine Coast Council)
• Land for wildlife weed control methods
• Vine control Bush Regeneration Techniques (YouTube | Landcare)
• How to control madeira vine on your property (YouTube | Logan City Council)
• Balloon vine control (YouTube | Pittwater Ecoworriors # 20, 720p.mpg)

Woody weeds can invade natural areas and can be costly to manage once they are fully grown. Follow up monitoring and control are essential for the success of any of the below control methods.

Manual removal

Trees can be cut at the base and roots can be dug out or removed by machine. Smaller trees and shrubs can also be removed with tree poppers. These are set up at the base of the plant and then using some manual pressure the roots are leveraged out of the ground. Council has tree poppers available for hire.

Cut and paint

Involves cutting the plant at the base with secateurs, loppers, a handsaw or chainsaw (depending on the size of the plant) and applying herbicide to the stump within 15 seconds (any longer than 15 seconds will affect results) to ensure that it is absorbed by the plant.

Basal bark

The basal bark method is useful for shrubs and trees up to 10cm in diameter, especially those that are multi-stemmed or with a suckering nature that are difficult to stem inject. It involves painting the bottom 30-40cm of the trunk all the way around with a mixture of oil soluble herbicide and an oil based carrier such as diesel, kerosene, bark oil or vegetable oil (as per specified mixing rates for basal bark method). This leaves the root system in tact which can help to prevent erosion.

Ring barking

This method involves removing the outer layer of a 20cm or more section of trunk all the way around the tree or shrub to prevent nutrients from being transported so that the tree or shrub dies. This method is only suitable where falling limbs of the tree will not cause harm to people, animals or structures.

Stem injection

This involved drilling or cutting holes just beneath the bark to the sap wood of the plant around the stem 5cm apart and filling them with herbicide. The herbicide is transported throughout the plant and eventually kills it. This method is only suitable where falling limbs of the tree will not cause harm to people, animals or structures.

Useful resources to help you get started

• Woody weeds of South east Qld: Shrubs and trees
• Groundsel bush (Invasive Plant Management – Groundsel bush)
• Weed control methods (LfW-Note-ENVIRONMENTAL-WEEDS-EW2_Weed-Control-Methods_WEB.pdf)
• Woody weed control (Bush Regeneration Techniques)
• Stem injection (Bush Regeneration Weed Control Techniques)
• Cut and paint (Bush Regeneration Weed Control Techniques)
• Broad-leaved pepper tree (Schinus terebinthifolius) ID and weed control video
• Privet control (Drill, fill and kill Privet!)
• Lantana Control Bush Regeneration Techniques
• Mexican bean tree identification (Cecropia Far North Coast Weeds)
• Bush regeneration techniques after fire (Get to know the six main weeding techniques: bush regeneration skills)
• Tree Poppers for Woody Weed Control
• Camphor Laurel Ring Barking Tutorial

There are four main types of aquatic plants free floating, floating attached, submerged plants and emergent plants. Water weeds out-compete native plants, clog up water ways, interfere with irrigation and deplete waterbodies of oxygen by blocking sunlight. 

Of all invasive plants, aquatics can be the most difficult to control as they are spread easily along waterways and seeds can remain viable for long periods of time. Identifying and preventing the establishment of water weeds is critical. Containment is a priority. This can be achieved by alerting neighbours about the presence of the weed and in some cases with a containment boom.

Manual removal

Involves manually removing weeds and is effective for smaller areas or when doing follow up control.

Mechanical removal

Involves using machinery such as an aquatic weed harvester to remove invasive plants from the water.

Foliar spray

This method is useful for treating most types of invasive plants apart from some succulents and trees. It involves spraying herbicide onto the leaves of the tree which is then absorbed into the plant. Foliar spray can be applied by a back pack sprayer for smaller areas or a quickspray unit for large scale weed control. Sunshine Coast council has back pack kits, quick spray units and containment booms for hire.

Useful resources to help you get started

• Aquatic weeds of South east Qld: Identify a Weed
• Aquatic Weeds | Sunshine Coast (YouTube)
• Frogbit (Fighting Frogbit in the MidCoast - YouTube)

Replanting areas once you have removed invasive plants will help to:

• stop erosion
• reduce the space available for invasive plants to get established
• create canopy cover
• attract native wildlife to your garden
• create cooler micro-climates on your property.

Here are some useful programs and resources to get you started

• Land for wildlife technical notes
• Land for wildlife
• Gardens for wildlife
• Landholder environment grants
• Native plants page 
• Native Plants Sunshine Coast 
• Native Plants Queensland 
• Community native nurseries page 

If you decide to use herbicides on your property please make sure you:

• use them in accordance with their label
• assess environmental factors (for example presence of native plants and pollinators)
• consider the impact on soil health
• assess surrounding land uses (proximity to waterways or food crops)
• assess weather conditions (wind and rain)
• choose the optimal application time
• consider the use of surfactants to increase the effectiveness of the herbicide
• use the correct personal protective equipment (PPE), and
• use them only as part of an integrated weed management approach.

To minimise the impact of herbicides on foraging insects, including bees:

• Use cut and paste method where possible to minimise the need for foliar spraying
• Don’t spray when plants are flowering (bees and other insects will be collecting pollen and nectar from flowers)
• Don’t spray on windy days when herbicides can drift onto other plants which are flowering and where bees are working
• Spray late in the afternoon when bees have finished foraging for the day.
• Adjust spray nozzle so droplets are bigger and therefore less likely to drift onto other plants
• Check if your neighbour is a bee keeper before spraying invasive plants
• Make sure you follow label instructions – stick to mixing rates on the label

The basal bark method is useful for shrubs and trees up to 10cm in diameter, especially those that are multi-stemmed or with a suckering nature that are difficult to stem inject. It involves painting the bottom 30-40cm of the trunk all the way around with a mixture of oil soluble herbicide and an oil based carrier such as diesel, kerosene, bark oil or vegetable oil (as per specified mixing rates for basal bark method). This leaves the root system in tact which can help to prevent erosion.

Bio-control is a method of controlling invasive plants using the plants' natural enemies such as insects. A rigorous testing process is undertaken to ensure that bio-controls are host specific before they are approved and released into the environment. Bio-controls reduce the need to use chemicals and also the cost of invasive plant management. Bio-controls have been released by the Sunshine Coast Council for Salvinia, Madeira vine, Cats claw creeper and Lantana.

Depending on supply and demand you may be able to purchase the following bio-controls from the places below

Bio-control for Cat’s claw creeper and Madeira vine are available from the Mooloolah River Waterwatch and Landcare Inc and Gympie District Landcare

Bio-controls for Salvinia, Water hyacinth and water lettuce from Brisbane City Council

This can be useful for vines, shrubs and trees. This method involves cutting the stem at the base of the plant with secateurs, loppers, hand or chainsaws (depending on the size of the plant). The roots can then be dug out or plastic can be wrapped around the stump of the plant to prevent regrowth.

This method is suitable for woody weeds such as shrubs, trees and vines. It involves cutting the plant at the base with secateurs, loppers, a handsaw or chainsaw (depending on the size of the plant) and applying herbicide to the stump within 15 seconds (any longer than 15 seconds will affect results) to ensure that it is absorbed by the plant.

This method is useful for treating most types of invasive plants apart from some succulents and trees. It involves spraying herbicide onto the leaves of the tree which is then absorbed into the plant. Foliar spray can be applied by a back pack sprayer for smaller areas or a quickspray unit for large scale weed control. Sunshine Coast council has back pack kits and quick spray units for hire.

Hand weeding involves pulling out invasive plants manually or with tools. Make sure that the whole roots, tubers, bulbs or corms are removed and any parts of the plant capable of reproducing, are bagged and solarised or disposed of. This method causes minimal disturbance to the soil and to other plants.

Mechanical options include using larger machinery to remove invasive plants. For example tilling the soil or using an aquatic weed harvester to remove invasive plants from the water.

Mowing, brush-cutting and slashing can be useful for controlling invasive plants by preventing flowering and seed dispersal. This method is not useful for plants that spread by stem fragments or those that flower and seed at different times throughout the year. Mowing these types of plants will spread stem fragments and seeds to other areas. This method is useful for annuals such as annual ragweed and can even be useful for groundsel bush if done annually prior to flowering. Timing is crucial for using this method for weed control.

Pasture improvement and revegetation will help to prevent invasive plants from becoming established or re-establishing, create habitat and prevent erosion where invasive plants have been removed.

Tree poppers can be used to remove woody plants such as shrubs, small trees or weedy vines. Tree poppers are set up at the base of the plant and then using some manual pressure the roots are leveraged out of the ground. Council has tree poppers for hire

Some invasive grasses such as Giant Rats tail grass produce significant amounts of seed. The seed heads will need to be cut and bagged before the rest of the plant is dug out.

This method involves removing the outer layer of a 20cm or more section of trunk all the way around the tree or shrub to prevent nutrients from being transported so that the tree or shrub dies. This method is only suitable where falling limbs of the tree will not cause harm to people, animals or structures.

Smothering invasive plants is usually done on a small scale using weed matting, cardboard or newspaper to suppress the growth of plants by preventing them from capturing sunlight. This is useful for groundcovers, grasses and some succulents.

Solarisation uses the suns heat and black plastic cover to control invasive plants and reduce the seed bank in the soil. To solarise invasive plants cover them in thick black plastic and weigh it down on all sides or use pegs to keep the plastic down. The plastic will stop light reaching the plants which will stop them from being able to photosynthesise and will trap heat which will reduce the amount of seeds able to germinate in the soil. The process takes around 2 to 4 months depending on the weather. Factors such as rain and temperature will affect the success of solarisation. Solarisation is not usually effective for deep rooted plants as the soil temperature is usually only hot enough in the top couple of centimetres.

Large vines, trees and shrubs can be stem injected. This involved drilling or cutting holes just beneath the bark to the sap wood of the plant around the stem 5cm apart and filling them with herbicide. The herbicide is transported throughout the plant and eventually kills it.

Wick wiping involves the application of herbicide by either a hand held or a rotating wick on a trailer, onto undesirable plants. The use of a trailer wick wiper is only appropriate for faster growing pasture weeds where a distance is able to be achieved between the invasive plants and desirable pasture species so that the wick only touches the invasive plants. A hand held wick wiper is useful for a variety of invasive plants including pasture weeds, ground covers and small shrubs. A hand held wick wiper allows a concentrated amount of herbicide to be wiped onto a plant. This technique is useful for pasture weeds. Council has both trailer and hand held wick wipers available for hire.

This method is useful for weedy vines and involves scraping off a section of the outer bark and applying herbicide within 15 seconds (any longer than 15 seconds will affect results). Wrapping plastic around the area where the herbicide has been applied can assist with the absorption of the chemical by the plant. The herbicide is transported throughout the plants vascular system killing it entirely. This method is useful for Madeira vine as it can easily regrow from stem fragments and therefore it is important to kill the whole plant.