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Thinking about chemical-free weeding on your site? Here’s what you need to know.

With uncertainty about the safety of using chemicals to control weeds, there is an increasing desire for chemical-free weed management. We offer various alternatives methods and techniques to manage weeds on site. 

Some of the alternatives that we have been implementing are:

  • Thermal Weeding
  • Physical removal
  • Habitat removal and alteration

Thermal Weeding

Thermal weeding is a method where high temperatures are applied to weeds, causing the plant to die. This technique is particularly useful in situations where conservation or health considerations are high and weed density is low such as waterways where herbicide use is not permitted.

The different thermal methods that can be used include:

  • Steam weeding
  • Flame weeding
  • Bio-thermal weeding

Steam Weeding

A steam weeder works by causing the temperature of water in plant cells to rise causing the cells to rupture. This causes the plant to die from the outside back to the root system. Steam weeding has been shown to be more effective at killing plants than flame weeding. However, they require a lot of water and energy to heat the water.

Flame Weeding

A flame weeder uses LP gas to produce a flame which produces enough heat to vaporise the water in plant cells. As a result, this moisture loss inhibits photosynthesis killing the weed. A flame weeder has also been shown to stimulate the germination of native plants, while killing the seeds of annual weeds such as Devils Pitchfork, Bidens pilosa. The only disadvantage to flame weeding is the cost of gas and the risk of fire.

Physical Removal

Physical removal of weeds is the control of weeds by either:

  • Hand/manual removal
  • Removal by animals e.g. chickens, goats, guinea pigs and bush Turkeys
  • Mechanical removal

Hand Removal

Hand weeding is useful where there is a sparse covering of weeds or where weeds are growing with desirable vegetation that is sensitive to herbicide.

Habitat Removal and Alteration

Covering and removing weed habitat can be achieved by:

  • Barriers including: mulching, on-site composting – high heat black plastic and shade
  • Planting: using pioneer plants and densely growing species to out reduce habitat for weed species.

Mulching

Mulching of garden beds, with materials such as crushed sandstone reduce the likelihood of weeds growing vigorously.  However, weeds will still grow if left unmaintained therefore ongoing mulching is required for optimal results (stone or wood).

Planting

Locally native species with dense growth can be planted to reduce habitat and outcompete common herbaceous weeds and grasses.

This method is most effective with maintenance such as hand removal of grass weeds from densely planted areas to assist in the natural spread of native plants.  In addition, mulch can be used to suppress weed growth in areas while the native species establish.

Other Lesser Known Techniques

Pressure-Water Weeding

High pressure water blasting method is a method for removing weeds by damaging, cutting and tearing their leaves and steams.

Foam Weeding

Foamstream is biodegradable foam made from natural plant oils and sugars. When applied to weeds together with hot water, the foam acts as a blanket, keeping the heat on the weed long enough to kill it. A wetting agent in the foam speeds up the transfer of heat into the weed’s cell walls.

Sugar, Salts and Pine Oil

Weed management by adding sugar, salts and substances such as pine oil to soil are in trial stages. Research has shown that adding these substances to soil increases carbon which in turn increases microbial populations and CO2 production while reducing soil nitrogen.  Since these characteristics are generally more beneficial to native Australian species over exotic species, it gives native species an advantage to outcompete exotic species. 

If you are looking for a safe and effective approach to managing weeds, contact us now for any enquiries!