The UK’s first integrated pest-management guidance for amenity use gives landowners an easy set of tools to analyse their pesticide use and reduce it should they wish to do so.
Weeds: Best Practice Guidance Notes for Integrated and Non-chemical Amenity Hard Surface Weed Control is the result of a five-year scientific study commissioned by Defra, run by East Malling Research and hosted by Kent County Council on the streets of Thanet. It studied amenity use of herbicide, non-herbicide and integrated approaches to weed removal.
The guidance is primarily aimed at local authorities, which represent two-thirds of amenity pesticide use, but can be used by others. The study only looked at hard surfaces because it had limited resources, but the Government hopes an integrated or non-chemical approach will be adopted by all.
The guidance advises adopting a four-stage approach: planning; determine appropriate treatment; contract procurement and implementation; and review progress.
Good planning will cut down on the amount of pesticide used from the start, the guide insists.
Using asphalt instead of slab, for example, cuts out cracks where weeds can grow and potentially cause problems to paving.
However, Kent County Council landscape officer David Mounter, who was involved in the study, admitted that there is a conflict with water-sensitive urban design, which encourages permeable paving — something that should be considered by landowners.
Crazy paving is best avoided. Careful mapping of an area of responsibility and then monitoring where more pesticides are needed is better than a blanket approach.
Using fewer resources in the areas where they are less needed can help to save money and time. Mapping also allows for easier identification of more vulnerable areas, such as proximity to surface water, groundwater boreholes, street furniture and parked vehicles.
Communication between stakeholders facilitates the co-ordination of weed control. For example, the guide notes: "Programming weed-control operations before street cleansing will ensure that dead foliage is removed to prevent detritus build-up."
Managing expectations is also important. "Having a weed-control policy available in an easily accessible format — on the local authority’s website — should help minimise the number of enquiries received and help to manage customer expectations."
Adopting an integrated approach will probably lead to increased treatments, the guidance suggests. "The use of herbicides is primarily to target persistent and inaccessible weeds.
Taproot weeds treated with mechanical or thermal methods can re-emerge after approximately two weeks.
"Therefore, in an integrated approach, spot treating weeds with a herbicide at the start of the growing season can be used. Rotating control methods is likely to improve control and reduce herbicide resistance".
When it comes to contract procurement and implementation, landowners are encouraged to combine weedkilling and street-sweeping contracts. They should consider long-term contracts to enable contractors to identify problem areas, target them efficiently and recoup the cost of investing in machinery, while landowners are advised to regularly monitor progress.
Contractors should have good reporting methods, preferably with GIS systems, so the asset data can be updated. Weekly updates and an annual review of the service are advised.
Determining whether to use a performance or frequency-based specification is also important. The former is risky, according to the guidance, whereas the latter can be adopted with an option to bring in extra treatments should they become necessary. Specifiers should consider only using members of the Amenity Forum or those who are Amenity Assured.
To assist with monitoring, the guidance includes a "weediness scale" that gives operatives, managers and specifiers an easy traffic light monitoring system to measure the extent of weeds on any given hard surface. This avoids unnecessary pesticide spraying that may have been specified in a contract.
There are three criteria and six levels that can be determined by the landowner at the outset. A level of weediness is arrived at by scoring each criterion separately then adding them together to determine an overall score and weed level.
The example given in the guidance — specifiers will decide their own weed comfort level — has green for levels one and two, yellow for level three and red for levels four-to-six. In this example green is acceptable, yellow indicates that action is required and red is unacceptable. Levels of acceptability will differ depending on local circumstances.
The authors of the guidance recognise that budgets "are a major factor in developing weed-control programmes". They aim "to provide managers and contractors with tools to develop more effective and efficient medium- to long-term integrated and non-chemical weed-management approaches, enabling the minimising of pesticide inputs".
Despite there being no legal push to persuade landowners to use less pesticide on their land, the UK must comply with the Sustainable Use and Water Framework Directives laid down by the EU. The UK Government’s preferred approach is to persuade and encourage the adoption of an integrated approach so that the nation cuts its use overall, the environment is preserved and the EU does not move to more stringent measures.
From the industry side, the Amenity Forum is keen to encourage best practice and the adoption of an integrated approach to head off any potential outright EU ban.
Speaking at the launch of the report, hosted by the Amenity Forum at Lantra’s headquarters in Warwickshire last month, Grant Stark of the Chemicals Research Directorate said the Government is not telling people what to do but giving them information to make an informed choice. The launch was "an incredibly important day", he added.
Stark and the guidance both point out that local authorities have an obligation to minimise pesticide use in public spaces and take "reasonable precautions to protect human health and the environment".
He adds: "Following an integrated approach and following the guidance show due diligence and we think it is ultimately the best chance of the UK meeting the requirements that exist."
However, some people attending the launch were sceptical about adoption. One contractor said: "There is zero chance of adoption by local authorities — they can’t afford it."
Another contractor pointed out managing expectations from the public can be a challenge. "They slag off chemicals but when you go the other way it’s ‘they haven’t done it’."
But suppliers of non-chemical solutions suggest the guidance will help to drive sales of alternatives. Weedingtech head of UK sales Fraser Higson says he expects local authorities to follow their continental cousins in adopting an integrated approach.
"We expect to see more and more organisations taking advantage of the opportunity this offers with Foamstream as the most cost-effective herbicide-free weed-control option across the whole weeding season, with fewer treatment cycles required and a more effective kill rate, sitting at the heart of an integrated approach.
"We welcome the move. It’s fantastic that there is now a clear framework in place for local authorities to address increasing public concern over the use of herbicides, as well as meeting growing pressure from the EU’s legislation, and we are thrilled to have played an integral role in the project."
Midlands firm Ubiqutek is currently trialling its non-chemical approach, which involves killing weeds with electricity. Several patents are pending. Its first product, a manual weeder that targets individual plants that is specifically designed for the amenity market, is due to launch this year.
Non-executive director David Mellor calls this method "an effective, versatile and safe alternative to herbicides". He adds: "We are in dialogue with a range of potential early adopters, including local authorities, but also covering utility companies, sports, heritage and zoological societies and soft-fruit growers.
"We held successful independent proof-of-concept trials last year and have extensive trials planned for our pre-production prototype this spring."
Mellor thinks the products, which he says will be produced in the UK, will also find a market abroad, with "the EU and North America key target markets".
Cardley-Wave, another system that is already popular in Europe, launched here last month. It uses water heated to 98°C delivered via manual and machine-mounted systems to kill weeds.
Manufacturers of non-chemical alternatives also point out that the costings used in the guidance, which show that changing from all-chemical to integrated systems costs twice as much and changing to non-chemical is eight times as expensive, will not stay the same as they continue to innovate.
Higson explains that Weedingtech has recently reduced the amount of Foamstream used by its machinery by around 40 per cent with the same results, while Mellor says his company is concerned that the guidelines can over-simplify and bundle together what is a diverse range of non-chemical alternatives and label them all with the same advantages and disadvantages.
"Our system, for instance, addresses many of the disadvantages mentioned in the report, hence we are concerned some of these findings could be set in stone before they can be challenged and disproved by new equipment," he explains.
The guidance is available at: www.emr.ac.uk
Alternatives - Other weed-control options
- Thermal Including hot foam, steam, hot water and weed burners using both infrared
- Mechanical/Manual Including brushing/ripping, mowing, strimming and weed pulling. Operatives must be trained in the use of equipment but do not require a pesticide specified certificate.
- Employers also need to be aware of health and safety implications such as vibrations as well as other issues such as vehicles obstructing larger vehicles and flammable objects such as wooden fences.
- Other In development or to be developed in the future, including electrical.