Pro Operator

Getting the most out of Avadex

Tractor and mounted sprayer applying Avadex

Avadex is a useful part of the black-grass control programme but needs careful application.

Avadex Excel 15G is an important ingredient in the herbicide stack to tackle blackgrass – it has no proven resistance problems in Europe and has a different mode of action to almost all other autumn herbicides used in the UK.

Including it in the programme is proven to enhance the overall performance of the ‘stack’ and it can be used on all varieties of winter wheat and winter barley. Avadex can also be applied under an EAMU to linseed, miscanthus, canary seed and rye and triticale.

As part of the Sustainable Use Directive (SUD), the UK government is required to show that UK growers are using integrated pest management practices. To view the integrated pest management plan from the VI, follow the link HERE

This involves using Avadex along with cultural control including crop choice and rotation, cultivations, drilling date flexibility and stale seedbeds. Avadex also needs careful application.

Applying Avadex

What you need to know about Avadex

Q: Does it need a special applicator?

A: Yes – the active is coated onto granules made from a very fine clay powder, which require the right fan strength, an accurate metering unit and distribution system. Do not use spinning-disc applicators.


Q: Does the applicator need to be tested?

A: Yes – under SUD rules since 26th November 2016 all applicators, more than five years old, required testing. New equipment has until its fifth anniversary to be tested for the first time. After 2020 they require retesting every six years. Link to SprayerTestingLeaflet pdf in folder


Q: Do I need to be qualified to apply?

A: Avadex (triallate) is a granular pesticide. Operators handling and applying the product need to hold a PA1 (Principles of Safe Handling and Application of Pesticides) and they will also require the appropriate application unit – PA4 G (Safe use of Granules).

Q: How do I apply it?

A: Avadex applicators can be mounted behind a drill, on a set of rolls, on an ATV, UTV or on a tractor.


Q: What rate do I apply?

A: 15kg/ha.


Q: When it is applied?

A: For spring barley it can be applied either pre-drilling and incorporated in the final cultivation pass, or ‘post plant, pre-emergence’ of these crops. For winter wheat and barley it can only be used ‘post-plant, pre-emergence’. Avadex can be applied in all soil conditions.


Q: Are there any crop safety issues?

A: If Avadex is applied behind the drill, winter wheat seed has to be sown at least 4cm deep.


Q: What are the pros and cons?

A: A range of applicators is now available with working widths up to 24m, which increases work rates. Applying Avadex behind the rolls will save an extra pass with an ATV or tractor-mounted machine, but soil conditions are not always suitable for rolling.

Applicator setting tips

Applicators need to be well maintained and equipped with the correct metering rolls for the product. They need to be calibrated to apply 15kg/ha and ideally tested for not only the application rate, but also the granule distribution, by a specialist engineer.

Check the machine regularly during use. Ensure the deflector plates are not damaged or twisted around and are mounted at the correct angle. Listen for air leaks along the distribution pipes – the spread pattern relies on the correct air pressure. Note pipes need to have a vertical down drop before the deflector plate – again for correct distribution.

If it is too windy to spray – it’s too windy to put on Avadex.


Set up for applying Avadex
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