How to use Stinger®


Stinger® Herbicide

Stinger is a broad spectrum woody weed, pasture, winter cereal and fallow herbicide. The label covers extensive list of woody weeds and a range of application techniques. It is an economical first strike for graziers and land managers with extensive infestations of blackberry. Stinger also offers broadacre growers in the northern grain region a residual tank mix product for use in winter cereals and fallow sprays.

Stinger – overview

Product key features

  • Cost-effective option for foliar spraying of large infestations of tough-to-kill woody weeds and many noxious or environmental weeds.
  • Acts on both weed foliage and roots to provide rapid reduction in total weed biomass.
  • Stinger is specifically designed to be used for biomass reduction as the first step (year 1) in a three-cycle, three-year pasture improvement program. Follow-up eradication treatments in year 2 and year 3 can then be effectively undertaken.
  • Leaf brownout and distortion of stem tips will normally be obvious within a week of application.
  • Controls the target weeds without harming most established grass pastures. (Note that ryegrass could be affected and the metsulfuron component could also damage some northern native grass species.)

Stinger description

The introduction of Stinger has enabled a new approach to weed control on properties where woody weed infestations are extremely large.

As noted in the key featuires above, Stinger is specifically designed to be used for biomass reduction as the first step (year 1) in a three-cycle, three-year pasture improvement program. Follow-up eradication treatments in year 2 and year 3 can then be effectively undertaken.

Product specifications

  • Ingredients:

    375 g/kg aminopyralid + 300 g/kg metsulfuron-methyl

  • Formulation:

    Water soluble granule

  • Pack sizes:

    200 g and 500 g

Major weeds controlled

  • Blackberry control
  • Docks control
  • Eucalypt regrowth control
  • Gorse control
  • Harrisia cactus (cacti) control
  • Lantana control
  • Paterson’s curse control
  • Ragwort control
  • St John’s wort control
  • Sweet briar control

Woody Weed Control Guide


Use the controls at the bottom of the page to get the most from this useful new tool from the Woody Weed Specialists.

Find out more

Stinger – application

Application methods

Apply as a foliar spot spray to completely wet all leaves and stems. Coverage should be to the point of run-off in that the chemical mix is just beginning to drip from the leaves once the spraying is completed. Think of painting a wall and use that motion in your spray action to achieve full coverage of the foliage, then use a more directed stream to thoroughly treat the stems and canes.

This type of application is called high volume spraying as you are applying a large amount of spray mixture to the target weeds. Provided that good coverage of the target weed is possible, high volume spraying can be completed using a variety of equipment – from a small hand pump unit to a knapsack sprayer through to a large motorised pump and hand gun unit.

With a foliar spray you are looking to capture enough chemical on the foliage to kill not only the above-ground portion of the weed but all of the root mass as well, so good coverage is essential. If you are spraying very large weeds like blackberries that are several years old, ensure that canes on the inside as well as the outside of the foliage mass receive direct contact with the applied spray.

As a guide, one hectare of blackberries 1–2 metres in height will typically require a spray volume of 3000–4000 litres to be thoroughly covered, whilst the same area of a small herbaceous weed such as ragwort will require 500–1000 litres. 

A video demonstrating the correct techniques for high volume spraying can be accessed here. 

Equipment required for application

  • Depending on the size of the job at hand:
    • Large dense infestations (for example large old dense blackberry stands) are best treated with a large motorised pump and hand gun unit or by helicopter. This equipment can often be hired or a contract spray applicator can be engaged.
    • However, a suitable knapsack or hand pump spray unit will suffice in many situations, provided that good coverage can be achieved (to the point of run-off).
    • Ideally use a spray unit that is dedicated for application of herbicides only (to avoid cross contamination).
  • Scales for weighing out correct amount of granules.
  • Measuring jug.
  • Cotton overalls or long-sleeved shirt and long pants.
  • Washable hat.
  • Elbow-length chemical-resistant gloves.

Application timing for best results

In general, smaller weeds are easier to control than larger ones.

Stinger is most effective when applied to weeds that are not stressed due to lack of moisture, excessive heat, insect damage, etc. and are actively growing. Actively growing weeds will draw the chemical into the vascular system and transport it through the stems and down to the roots to ensure maximum efficacy.

A general guide to the best time of the year in which to treat common woody weeds can be found in this table.

Stinger needs to penetrate into the leaves of treated weeds before any rainfall occurs so do not make applications if rain is possible before the spray is completely dry – usually one hour. Similarly, avoid application if the leaves are wet from rainfall or dew.

Once the weeds have been sprayed, leave them undisturbed so that the chemical is able to move throughout the leaves, stems and roots and provide complete kill. Disturbing the weeds by slashing, burning, mulching, etc. before the chemical is fully distributed will compromise the control achieved. We recommend that blackberries and other woody weeds not be disturbed for six months after spraying to maximise the performance of Stinger.

Application rate

For most weeds the rate of Stinger to apply is 20 g per 100 litres of water.

Always check the label for the correct rate. A copy of the label can be accessed here.

Stinger must be applied with a wetting agent or penetrant to maximise performance. If spraying gorse, use Pulse® Penetrant with Stinger. For all other weeds use a non-ionic wetting agent such as BS1000®. Complete instructions on which surfactant to use are detailed on the label.

Correct mixing procedure

Where possible mix Stinger with clean water sourced from town supply or a rain water tank. Clean dam or river water may be used as long as it is not high in metal ions such as magnesium and calcium or ions that bind to the chemical and reduce herbicide efficacy.

Quarter fill the spray tank with water and then add the Stinger, ensuring continuous agitation occurs. If only limited agitation is possible, pre-mix Stinger with water in a bucket then add to the spray tank. Maintain agitation within the tank and complete filling with water. Add the required surfactant once the spray tank is full.

Once mixed, the spray solution must be kept agitated and, ideally, used immediately. The mixture must be applied within 24 hours, as breakdown of the chemical will occur beyond this time.

Stinger – safety

Safe handling

Stinger is classed as a Poison and must be kept out of the reach of children.

The product can irritate the eyes and skin so take care when measuring it out and adding it to the spray tank. If any of the granules or the spray mix do get into your eyes or onto your skin, wash immediately with clean water.

Wear suitable protective clothing when measuring out the product, such as overalls or a long-sleeved shirt and long trousers along with a washable hat and elbow-length chemical-resistant gloves. Wash all clothing after use. Although the label does not specify any PPE when spraying it is good practice, especially as you are wearing the clothing as specified for mixing etc., to wear the same clothing and gloves when applying Stinger.

A copy of the Safety Data Sheet can be accessed here. 

Safety to stock

1. Grazing for meat production

Do not graze treated pasture within 56 days of application.

If feeding does occur within the paddock inside the 56-day period, the stock must be fed on clean feed (from outside the treated paddock) for at least three days before going to market.

2. Grazing for milk production

Do not graze treated pasture within three days of application.

3. Cutting pasture for animal feed 

Do not cut treated pasture for feed within 56 days of application.



Impact of Stinger on the environment

Health and safety profile sheet

Many desirable crops and ornamentals are very sensitive to Stinger so care must be taken when applying the product to ensure that there is no spray drift on to desirable plants or soil containing roots of desirable plants. A light but steady breeze directing any spray mist away from desirable plants is the ideal spraying condition. Avoid application when the wind direction is towards desirable plants or there is no breeze at all. In seemingly still conditions, spray mist can drift for long distances and in many directions, which can cause plant damage when it settles.

Plants susceptible to Stinger include (but are not limited to) fruit trees, grape vines, legumes (pea, beans, lucerne, etc.), potatoes, roses, shade trees and tomatoes.

Residues of Stinger can remain active in the soil for many months with the longevity affected by use rate, soil type, temperature and moisture. Care therefore needs to be taken when planting new crops or trees into areas where Stinger has been sprayed to ensure that no residues remain active.

Residues of Stinger can also remain in treated plant material for extended periods so do not use treated plant material to make compost or mulches. Manure from animals grazing on treated pastures should not be sold off-farm or used as compost within gardens.

Stinger may be used around waterways but spray should never be applied to water, or soil within a dry water course, or allowed to drift into or drip off treated foliage into water.



Cleaning spray equipment

After spraying is complete, thoroughly clean the spray unit to ensure no residues remain that may cause damage to desirable plants when the equipment is next used. Empty the spray unit completely and drain the whole system. Wash the tank, pump, lines, hoses and nozzles with a mix of water and chlorine bleach. Reassemble the unit, half fill with clean water and circulate through the pump and hose. Drain and repeat the rinsing procedure.

Ensure rinse water is disposed onto a designated area or an unused area where there is no risk to desirable plants.

Woody Weed Specialist