How to use Tordon® RegrowthMaster



Tordon® RegrowthMaster Herbicide

Tordon RegrowthMaster is an updated management tool to assist graziers in thinning regrowth to improve productivity of grazing enterprises and assist with native forest management. Through its specialised application technques, Tordon RegrowthMaster provides targeted weed control with minimal off-target risk.

Tordon RegrowthMaster – overview

Product key features

  • Specialty herbicide for use as a stem injection and cut stump treatment to control a range of woody weeds.
  • Formulated to be mixed with water.
  • Through the specialised application techniques, provides targeted weed control with minimal off-target risk.
  • Use provides excellent control of single- and multi-stemmed saplings where foliar spraying would be difficult or pose a risk to the environment.
  • Via cut stump treatment, prevents regrowth of trees following mechanical control.
  • May also be used as a high volume foliar spray for some species where the use of ester formulations is restricted.

Product description

The latest evolution in the long history of Tordon, with the addition of the powerful active ingredient aminopyralid, Tordon RegrowthMaster is used for targeted/selective thinning of timber via the stem-injection technique. In addition, this product offers an alternative to Access + diesel or Biosafe for cut stump control of woody weeds.

Product specifications

  • Ingredients:

    200 g/L triclopyr + 100 g/L picloram + 25 g/L aminopyralid

  • Formulation:

    Soluble liquid

  • Pack sizes:

    5 L and 10 L

Major weeds controlled

  • Acacia species
  • Casuarina species
  • Eucalyptus species
  • Melaleuca species. 

The full list of weeds controlled by Tordon RegrowthMaster is shown on the product label, which can be accessed here.

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

Tordon RegrowthMaster – application

Application methods

Mix with water and apply via stem injection or cut stump method.

a) Stem injection application

Make injection pockets (horizontal cuts) at waist height using a small axe with a 5–7 cm blade. The cut must be through the bark and sufficiently deep so that the injected chemical will be in contact with the sap but not so deep as to penetrate the heartwood. Leaving the axe in the tree, inject the chemical using a vaccinator set to deliver 1 mL (or 2 mL) so that the chemical runs down the blade into the injection pocket, remove axe and repeat (see video demonstration, link below).

Injection pockets should be formed around the circumference of the sapling with the distance between the centre of each cut being between 10 and 15 cm. Inject 1 mL/cut for regrowth less than 30 cm diameter when measured at the base. Inject 2 mL/cut on larger regrowth.

Take care on small diameter saplings to ensure that the injection pocket is not made too wide so that injected chemical runs out of the side of the cut. Injection pockets should also be staggered (not made at the same height) to avoid creating a weak point at which the top growth will break away in strong wind.

Stem injection can also be made using a basal tree injector such as the one produced by Tree Spear Pty Ltd – see here for more information.

A video demonstrating the correct technique for stem injection application can be accessed here. 

b) Cut stump application

First, cut the tree/sapling leaving an exposed stump. All stems should be cut less than 10 cm above the ground and horizontal to the ground to prevent chemical run-off. Cut and treat all suckers below the main stem cut height.

Using a knapsack or small pressure sprayer, apply the spray mix to the cut surface of the trunk ensuring that the sprayed surface is thoroughly wet. The cut surface is the sole access of the mixture into the plant. It is important that the spray mix be applied IMMEDIATELY after the stem is cut to maximise the penetration into the stump.

A video demonstrating the correct technique for cut stump applications can be accessed here. 

Equipment required for application

  • Suitable knapsack or small pressure pump spray unit (for cut stump applications).
  • Small (3/4 length) axe (for stem injection).
  • Vaccinator with tree injector kit (for stem injection).
  • Measuring jug.
  • Cotton overalls or long-sleeved shirt and long trousers.
  • Washable hat.
  • Elbow-length chemical resistant gloves.
  • Safety glasses, goggles or face shield.

Application timing for best results

Tordon RegrowthMaster is most effective when applied to weeds that are not stressed due to lack of moisture, excessive heat, previous herbicide treatment, etc. and are actively growing with active sap flow. Actively growing weeds will draw the chemical into the vascular system and transport it down to the roots to ensure maximum efficacy. Provided the target weeds are not stressed, application of Tordon RegrowthMaster via either treatment method can occur throughout the year.

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

Application rate

a) Cut stump application

Use 50 mL of Tordon RegrowthMaster in 10 L of water and always check the label before use. A copy of the label can be accessed here.

b) Stem injection application

Dilute at 1:4 in water and depending upon the sapling size, apply 1–2 mL of the mix per injection pocket (cut). Always check the label for the correct rate. A copy of the label can be accessed here.

Correct mixing procedure

Where possible, mix Tordon RegrowthMaster 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. Fill the spray unit with water then add the Tordon RegrowthMaster and agitate well.

Only mix enough Tordon RegrowthMaster for each day’s work and use the mix within 24 hours.

Tordon RegrowthMaster – safety

Safe handling

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

The product can irritate the eyes and skin, particularly in the concentrated form, so take care when measuring it out and adding it to the spray unit. If any does splash into your eyes or onto your skin, wash immediately with clean water.

Wear suitable protective clothing when measuring out the product and when spraying, such as overalls or a long-sleeved shirt and long trousers, along with a washable hat, elbow-length chemical-resistant gloves and safety glasses, goggles or a face shield. Wash all clothing after use.

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

Safety to stock

Tordon RegrowthMaster poses little hazard to stock and the method of use means that there is no stock grazing withholding period where stock are destined for slaughter for domestic markets. This means that stock can graze within paddocks containing treated weeds during and immediately after application.

However, an export grazing interval (EGI) of 42 days or an export slaughter interval (ESI) of three days must be observed if stock are destined for export slaughter. Alternatively, an export animal feed interval (EAFI) of 42 days can also be observed.



Impact of Tordon RegrowthMaster on the environment

Many desirable crops and ornamentals are very sensitive to Tordon RegrowthMaster so care must be taken when applying the product to avoid contact with desirable plants.

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

Heavy rain immediately after application via cut stump may wash some of the herbicide into neighbouring soil. Care therefore needs to be taken when planting new plants, trees or crops into areas where Tordon RegrowthMaster has been applied.



Cleaning spray equipment

After application 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 an alkaline laundry detergent such as Omo® or Drive®. 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.