Glyphosate resistance has reached the UK.

Glyphosate resistance has reached the UK. The new amenity guidelines point to prevention as WRAG and the Amenity Forum produce new guidance.

 · 5 min read

Glyphosate resistance has reached the UK. The new amenity guidelines point to prevention

Mechanical weed prevention on a hard surface with Kersten equipment

In 2025, the UK confirmed its first glyphosate-resistant weed populations, in Italian ryegrass on arable land. For anyone managing weeds on pavements, car parks and hard surfaces, that should be a wake-up call. Glyphosate is the most-used herbicide in amenity weed control, and the conditions that drive resistance are common in our sector.

On 8 October 2026, the Weed Resistance Action Group (WRAG) and the Amenity Forum published updated Guidelines for managing glyphosate resistance risk in amenity weed control (UK). The guidance was updated by James Clarke (WRAG Chair), Lynn Tatnell (Principal Weed Scientist, ADAS), John Cussans (ADAS) and Barrie Hunt, building on the original amenity guidance from 2009. It was launched at the Amenity Forum Annual Conference at the British Motor Museum, Gaydon. Its central message is blunt: the risk of glyphosate resistance in amenity situations is high.

Why amenity is high risk

Hard surfaces are often treated again and again, with no cultivation and very little soil disturbance. Every plant that survives a treatment can set seed and pass on its tolerance. Repeat spraying of the same survivors is, in the guidelines' words, the situation that "presents the highest risk".

The six key messages

  1. Glyphosate resistance is now present in UK agriculture.
  2. The risk of glyphosate resistance in amenity situations is high.
  3. Use glyphosate at the correct dose, on small, actively growing weeds, in optimum conditions.
  4. Make sure glyphosate use sits within an integrated pest management (IPM) or integrated vegetation management approach.
  5. Monitor and act on survivors.
  6. Consider resistance testing of survivors if needed.

The most important practical instruction is about survivors: "Do not retreat surviving weeds with glyphosate!" Remove them instead, so they cannot spread. The guidelines also stress using full recommended dose rates, because reduced rates are proven to increase resistance risk.

Brushing and sweeping are now part of resistance management

What stands out for us is how clearly the guidelines link resistance to prevention. They advise users to "plan to apply the herbicide following brushing or sweeping or, ideally in rotation with brushing or sweeping regimes." Removing small weeds and the build-up of debris means larger weeds are less able to survive treatment. Litter can shield weeds from spray, and dust can reduce how much herbicide a plant takes up.

They also note that mechanical techniques "can provide very effective control of small annual weeds", while control of perennials can be limited unless their roots are removed.

Kersten UBS carrier with WKB 60 weed brush restoring a path edge
Mechanical extraction and path edge restoration with a Kersten UBS and WKB 60 weed brush.

Launched at the Amenity Forum conference

Around 80 people from across the sector attended this year's conference, themed "Navigating Change: Regulation, Stewardship and the Future of Amenity Management" (Landscape & Amenity report). James Clarke, Chair of WRAG, said that "managing the risk of resistance is about good stewardship", and Ian Graham, Chair of the Amenity Forum, said that protecting glyphosate's "continued effectiveness depends on responsible use and good stewardship" (Landscape & Amenity).

Lynn Tatnell of ADAS presented the guidelines. Her presentation featured Kersten weed-brushing equipment to illustrate preventative brushing, and discussed the role of soil depth in weed establishment. It was good to see that link made so clearly in front of the sector.

What the Bracknell trial adds: depth decides which weeds survive

The guidelines explain why brushing helps. Our Integrated Weed Management Trial with Bracknell Town Council and Complete Weed Control adds evidence on when it matters most.

Bracknell Town Council Integrated Weed Management trial

Across six urban sites and 502 species-depth measurements, we found that the weeds growing on hard surfaces are strongly stratified by the depth of accumulated detritus, the soil-like material that builds up in joints, kerbs and channels. That relationship is the basis of a four-stage framework, set out in full in our scientific paper on Pavement Ecological Succession.

Depth decides which weeds survive Detritus build-up in a paving joint, Bracknell Integrated Weed Management Trial (Kersten UK) Stage 1 Up to 10mm Moss and pioneers. No anchorage. Sweep resets it Stage 2 11–25mm Roots float in the detritus. Brush lifts it whole Stage 3 11–25mm Roots anchored into the joint. Top breaks, root regrows Stage 4 Over 25mm Woody roots into the sub-base. Surface damage Window open: act here, before roots anchor Window closed: harder to kill, more to repair
The four stages of Pavement Ecological Succession, from the Bracknell trial.
StageDetritus depthRoot stateWhat it means
1. PreventionUp to 10mmSurface only, no anchorageA routine brush or sweep resets the surface
2. Window open11–25mmFloating in the detritusBrushing lifts the whole plant, root and all
3. Window closed11–25mmAnchored into cracks and jointsThe top breaks off; the root stays and regrows
4. Structural failureMore than 25mmWoody roots into the sub-baseSurface damage; repair rather than maintenance

Stages 2 and 3 share the same depth, so depth alone can't tell them apart. A simple Kick Test can: if the plant and detritus move as one unit, the window is still open.

This matters for resistance. Stage 3 and 4 plants are established, often perennial, with roots protected in the surface. They are exactly the large, hard-to-kill weeds the guidelines warn are most likely to survive treatment. Keeping surfaces at Stages 1 and 2 means any herbicide that is still used meets small weeds on clean surfaces, as the guidelines recommend.

The trial also measured how much herbicide was needed. At the first application in June 2026, across five comparable sites, plots that were brushed before spraying used 1,133ml of active substance, against 2,218ml on spray-only plots: a 49% reduction. Removing the detritus first reduced both the area and the amount of weed that needed treating. The full end-of-season results will follow.

Brushing first halved the herbicide needed Active substance used, first application, June 2026, five Bracknell trial sites Spray only 2,218 ml Brush, then spray 1,133 ml 49% less Source: Bracknell Integrated Weed Management Trial (Bracknell Town Council, Complete Weed Control, Kersten UK). End-of-season results to follow.
Brushing before spraying cut the active substance needed by 49% at the first application.

We've written more about this in The 25mm Rule: Time & Depth Determine Weed Control Success.

What to do now

  • Brush or sweep first. Build regular detritus removal into your programme, and time any herbicide to follow it, as the guidelines recommend.
  • Keep surfaces shallow. Aim to keep detritus below 10mm, and act on sites in the 11–25mm band before roots anchor.
  • Never re-spray survivors. Remove them mechanically and record where they were.
  • Check results after every application. Good records help you spot any loss of control early.
  • Rotate methods. Brushing, thermal and chemical control used in sequence reduce the pressure that selects for resistance.
  • Test if in doubt. Suspected resistance can be checked through an adviser or ADAS (weeds@adas.co.uk).
Kersten Weedo II pedestrian weed brush
The Kersten Weedo II pedestrian weed brush.

Resistance gives councils and contractors one more strong reason to move from reactive spraying to prevention. If you'd like help assessing your sites or building brushing into your programme, see our mechanical weed removal range, our National Action Plan guide for councils, or talk to our team.


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Frequently Asked Questions

Glyphosate resistance refers to weeds developing tolerance to the herbicide glyphosate. The UK confirmed its first glyphosate-resistant weed populations, specifically Italian ryegrass on arable land, in 2025. This is a significant concern because glyphosate is the most widely used herbicide in amenity weed control, and its continued effectiveness is vital for managing weeds on hard surfaces like pavements and car parks. The development of resistance threatens this crucial tool for weed management.

Amenity situations are high risk because hard surfaces are frequently treated repeatedly with glyphosate, often without cultivation or significant soil disturbance. This environment allows plants that survive a treatment to set seed and pass on their tolerance. The guidelines explicitly state that repeat spraying of the same survivors presents the highest risk for developing and spreading glyphosate resistance, making prevention critical in these areas due to the specific conditions.

The updated guidelines from WRAG and the Amenity Forum emphasize prevention. Key messages include using glyphosate at the correct dose on small, actively growing weeds in optimal conditions, and integrating it within an Integrated Pest Management (IPM) approach. Crucially, they advise monitoring and acting on survivors by removing them instead of re-treating with glyphosate, as well as considering resistance testing of survivors if needed to confirm resistance.

Brushing and sweeping are now recognized as important for resistance management by linking prevention to herbicide application. The guidelines advise applying herbicide after brushing or sweeping, or ideally in rotation with these regimes. Removing small weeds and accumulated debris means larger weeds are less likely to survive treatment. Mechanical techniques are very effective against small annual weeds, and trials have shown brushing before spraying can significantly reduce the amount of herbicide needed.

To prevent glyphosate resistance, it's recommended to brush or sweep surfaces first and build regular detritus removal into programmes, timing any herbicide application to follow. Keep surfaces shallow, aiming for detritus below 10mm. Critically, never re-spray surviving weeds with glyphosate; remove them mechanically and record where they were. Also, check results after every application, rotate control methods, and consider testing if resistance is suspected.