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removal and treatment
of Japanese knotweed



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In the Pre-Contract Enquiry form (TA6) there is a specific question asking the seller ‘if the property is affected by Japanese knotweed?’. If the seller fails to disclose Japanese Knotweed or knowingly falsifies the non-presence of Japanese Knotweed to the buyer, a claim against the seller could be brought before the courts for ‘Misrepresentation’.
Under the Consumer Protection Regulations, agents acting on behalf of the seller have a duty to disclose any “material facts”. Guidance to the regulations now includes Japanese knotweed as a material fact.

Unfortunately yes it does. If it has been treated with any kind of pesticide, there is a high possibility the rhizome will go into dormancy, making it more difficult to detect the scale of the Japanese knotweed infestation & to give the infestation the appropriate amount of treatment in subsequent visits.

If there have been attempts at digging or removing the Japanese Knotweed, it will be very difficult to recognize the original extent and spread of the plant.

Japanese knotweed infestations vary considerably from property to property and therefore each site is considered and treated as unique. A site survey is essential in order for the knotweed surveyor to assess and report on:

  • The full extent of the knotweed including its rhizome system
  • The likely source or origin of the knotweed
  • The status of the knotweed in relation to its maturity, whether active or dormant
  • The location in relation to knotweed encroachment issues with adjoining land
  • Whether the building has possibly been damaged by knotweed
  • Site specific conditions that might influence the treatment methodology
  • RICS  (Royal Institute of Chartered Surveyors) Assessment Framework Classification (inc 7m buffer zone)

An initial Site Survey is undertaken reporting on the above factors, but also outlining the presence of any other invasive plants or ecological issues. The issues are mapped using the latest mapping technologies and a site map, identifying the location and a 7m buffer zone is included. A report is written with time/date stamped photographic evidence from site and is submitted to the client with recommendations for consideration. To comply with current regulations, we follow strict guidelines before carrying out any work. This includes Risk Assessments.


This is the responsibility of the PCA approved surveyor attending site who can give clear direction of a robust treatment programme & management plan. All products will be given approval supported by up to date formulation carrying current legal recommendations. Find out more about our Japanese Knotweed Surveys.

A detailed 5-year management plan including site description, management objectives, levels of infestation, programme of works, treatment recommendations, as well as actions to be taken to prevent further spread etc is created.

Knotweed Services are employed to take full responsibility of the Japanese Knotweed infestation.

As well as providing the treatment, we also provide all the required documentation.

The 5-year management plan is comprised of:

  1. 3-year Herbicide treatment plan consisting of X2 visits per year
  2.  2 years of monitoring the site for any regrowth

Following the 3 year treatment, once treatment appears to be successful, we continue to monitor the site for a further 2 years in accordance with the Property Care Association (PCA) Code of Practice. No regrowth must be observed for X2 years before a completion certificate is issued.

  1. A final inspection & Completion Certificate
  2. 10 Year Warranty & Insurance Backed Guarantee (IBG) packages available upon request

As we are a PCA approved contractor, this management plan is fully compliant with industry standards and is recognised by banks and building societies to allow lending against a property.

As previously identified, infestations vary considerably property to property and therefore the application technique will too. It may be necessary to use only one method of treatment or the combination of different methods. As this is nature we are dealing with, our Japanese Knotweed specialists are trained to factor in all considerations in order to achieve optimal results.  Decisions with regards to the methods of treatment opted for, will ultimately be decided by the ongoing assessment of site-specific infestations and the influencing factors/variables previously discussed.

Therefore, the application procedure, giving the maximum efficacy with minimum waste and environmental impact will be tailored to specific sites.

As PCA approved Japanese Knotweed specialists, we are also guided by the latest research and development which gives guidance to the optimal time for treatment.

The latest research from Swansea University, released April 2018 by Dr Dan Jones & Professor Dan Eastwood found that:

‘applying the wrong herbicides at the wrong time of the year, leads to greater herbicide use and environmental impacts.  The 4-Stage Model that we have developed links herbicide selection and application with the seasonal surface-rhizome flows in the knotweed plant.  This seasonal targeting of knotweed delivers better results and uses lower doses of herbicide across the whole treatment lifecycle.  For the public and land managers, this means more affordable treatment that is also more environmentally friendly than traditional, blanket herbicide application.” (Dr Dan Jones-Swansea University).

Following the release of this research, Knotweed Services (UK) Ltd now operate using the 4-stage model which identifies the optimal time for treatment.


The most common herbicide application is to spray the foliage. We use powerful chemicals with the use of a knapsack. Chemicals are sprayed away from other plants to ensure that other plants aren’t damaged. The most effective time to apply foliar spraying to Japanese knotweed is in Spring.

This is much more damaging to the underground rhizome system than applying herbicides in any other season. A qualified person should carry out any treatment that involves the use of chemicals due to their powerful and harmful nature.

All of our PCA trained and approved technicians are NTPC qualified and have gained-

PA1 Safe Handling & Application of Pesticides

PA6A Use of Hand Held Applicators on Land

*PA 6AW Use of Hand Held Applicators on Land & Near Water

*Knotweed Services (UK) Ltd work closely with the Environment Agency to ensure an ‘Application to use Herbicides in or near water’ is applied for before the commencement of works near water courses.


With this treatment we employ a device to ‘physically wipe’ our chemicals onto the Japanese Knotweed leaves directly.

This means our application is precise and that we can often use a higher concentration of chemical.

Wiping has advantages over spraying – the chemicals are being absorbed directly by the Knotweed and there’s less wastage and drip.

It’s also a better solution if the infestation is very near desirable plants and foliage (no matter how careful we are, droplets in sprays can drift).


we apply a controlled amount of herbicide directly into the Japanese knotweed plant. Due to being injected directly into the plant, this is the most crafty method of removal. Unlike other spraying methods (more traditional) it is not dependant or compromised by weather conditions.

With traditional spraying methods, the environment has to be taken into account because rain or wind could cause the chemicals to spread to other species and have the potential to be harmful. Due to the nature of the stem injection procedure, it is 100% safe.


Crown and stems are capable of regenerating and even small fragments of cut crown or stem are capable of regenerating and becoming a new plant – removing these from the equation is a great strategy.

New plants will grow from the nodes of pieces of green stem, in soil or water. Mechanical cutters will spread knotweed in this fashion. If stems are dried until they are dark brown, they will not regrow unless the crown (base of the stem) is still attached.

Crown removal is exactly what you would expect from the title. By removing the crowns of the Japanese knotweed plant, we remove the majority of biomass that is underground. With the crowns removed – our herbicide and stem injection treatments are much more effective. All material is removed off site and disposed of correctly as we hold a Waste Carrier License and follow the current legislation for the disposal of ‘controlled waste’.

When arriving on site, our staff can be identified from the ID badges they wear and are equipped with Knotweed Services (UK) Ltd branded vans; which have the latest tracking devices installed; and a range of the latest treatment equipment and tools, fencing and signage. Vans are also stocked with ‘Chem Safes’ for the safe transport of herbicides and staff are equipped with the necessary PPE to conduct their work thoroughly and safely.

All technicians are also equipped and operate with the latest tablets, with internet connection, so all data collected from site is automatically uploaded to our CRM system.

Ongoing monitoring of the infestation site to include follow-up inspections, updated reports and photo documentation. When the infestation is under control a signing off certificate is issued.

All of Knotweed Services (UK) Ltd documentation are in electronic format and are within our bespoke CRM database system; which can be accessed via the cloud. The system is accessible by all technicians and administration staff. Certain documents/notes can be made available( upon request) to all customers. The system is backed up and is stored on secure servers.

When booking a survey, the information required would include:

Name, address, contact details (inc telephone no. & email) site details, access issues and some questions specific to the JKW infestation on the property/site and the history of any previous treatment.

It is very important that any JKW infestation is allowed to grow during the spring/summer season as our methods of treatment have more impact after this time.

We follow the 4 stage Model which is based on the very latest conclusions drawn from the research conducted by Swansea University, released April 2018. Based on the results of the research, there is an optimal time to apply herbicides in order for them to

  1. Have the most impact.
  2. Reduce herbicide use and therefore reduce the environmental impacts.
  3. And finally, ultimately reduce costs due to the decrease in the ‘typical’ blanket herbicide application.


All relevant parties, who work on your land, will need to be advised regarding the presence of Japanese Knotweed infestations. All relevant parties would also need to be notified that the cutting down/pulling out of any Japanese Knotweed is not permitted during the treatment programme as to do so would severely hinder the control of the Japanese Knotweed, or worst-case scenario cause new infestations to occur.

A 1m boundary should be left around the infestation to avoid contaminating surrounding soil & it is imperative that no Japanese Knotweed is permitted to be disturbed, broken / pulled during our in-situ control programme as this could potentially delay our timescale and potentially increase our control costs.

Japanese Knotweed is capable of growing 6cm per day and is found throughout the UK. It is highly invasive and has the capability to regenerate from rhizome as small as 0.4g, therefore there is a highly substantial risk of spreading the plant via groundwork and disturbance.

To provide advice and guidance, Knotweed Services have published a Japanese Knotweed brochure/company brochure, which outlines what JKW is, what it looks like, the treatment process, the clients responsibilities, do’s & don’ts etc. Clients need to be made aware of potential actions which could potentially jeopardise any treatment plan, which could potentially result in the regrowth of JKW.

Click here to read our brochure online.

As we are dealing with nature, a fundamental part of any successful treatment plan is the ongoing assessment conducted by our highly trained, qualified surveyors/technicians. The assessment of previous treatment & the methods used is continuously assessed to ensure a successful outcome. It is during this ongoing assessment that any necessary changes in methodology or number of applications is identified as a ‘one fit, does not fit all’ and each infestation must be looked at independently. Any changes to methodology or additional visits required will be discussed with the clientil and agreement to ongoing treatment will be sought based on the assessment of individual sites.

Every visit/treatment conducted is recorded by our staff in the form of a ‘Treatment’ record with details including:

  • Date and time of visit
  • Surveyor/technician details
  • Log- detailing any growth, methodology used, factors/variables & considerations to treatment
  • Photographic evidence
  • Recommendations

Each visit conducted and the completed paperwork is recorded for each specific site, on our CRM so all details are stored in one, accessible place and any information relating to any specific site can be easily accessed at any given time.

Final Site Visit

Following the successful management plan of X2 treatments over a 3 year period , Knotweed Services will continue to monitor each site for a period of X2 years to monitor for regrowth. 2 years of no regrowth is required before we issue a Completion Certificate.

On the final site visit, a completion certificate, 10-year site warranty and guarantee will be issued.

10 Year Warranty & Insurance Backed Guarantee (IBG) packages available upon request.

Insurance Backed Guarantee (IBG) is provided through Guarantee Protection Insurance Ltd (Accelerant Insurance UK Limited) which is an independent insurance company approved by the PCA trade body.

Accelerant Insurance UK Limited offer 2 types of IBG’s. The Complete Package or Knotweed Express.

Knotweed Services operate a free service for the identification of Japanese Knotweed.

This service has several advantages. Early identification of JKW is by far the best outcome given how JKW spreads so rapidly and easily; and this also helps to combat excessive treatment bills.

Knotweed Services have several various platforms available for individuals to upload photos for identification, including:

Knotweed Services would also recommend the following consideration of ‘why wait to discover if properties have JKW? Are third parties managing the garden? Could they be unknowingly cutting it/pulling it down not knowing what JKW is?  We would certainly recommend use of our free literature to inform tennants/owners of what JKW is, what it looks like and to engage with our free identification service if in doubt.

Knotweed Services ensure that the company and staff operate under strict guidance and compliance of Industry standards to achieve the best results in terms of quality and service and to ensure we are operating in a safe capacity as a company and ensuring environmental awareness.

PCA Membership

Japanese Knotweed control is a difficult and specialist service. For successful Japanese knotweed removal and control for both residential and commercial sites, professional identification, surveying & treatment (including the legal disposal of controlled waste) should be entrusted to the professionals.

Knotweed Services (UK) Ltd is a registered, approved PCA contractor, thus ensuring our bespoke treatment and removal management plans, within the Residential and Commercial sectors, are fully compliant with industry standards and are recognised by all banks, building society’s and lenders to allow lending against a property.

The Property Care Association (PCA®) is the trade association representing specialists across the UK who can be trusted to resolve problems affecting buildings.

In order to become members of the PCA, we have met strict membership criteria to demonstrate our companies technical competence and service delivery standards and can investigate and resolve property defects.

Companies wishing to join the PCA are required to meet and maintain robust membership criteria.  These criteria cover aspects of their services including professional qualifications, technical competence, service delivery and financial stability.

In order to maintain membership of the PCA, member companies also have to maintain these standards, and are audited regularly to ensure standards are being maintained.  This gives consumers confidence that PCA members are robust and reliable companies to provide them with property care services.

The PCA also provides an industry voice on behalf of its members and the sectors it represents.  The PCA works with government departments, industry bodies, responds to

industry consultation documents and assists with the development of new guidelines, all with the aim of promoting best practice and protecting consumers.

Controlling Risk at Work

Risk Assessment at each site is paramount to identify and raise awareness of any risks or hazards.

The job description & infestation details are documented, treatment procedure options are considered & factors which may influence these are as follows:

  • Environmentally Sensitive Areas
  • Water Courses-(‘Application of herbicide on or near water’ and close consultation with the Environment Agency is required)
  • Housing/habitable space/outbuildings/garage
  • Footpaths/Public footpaths/highways
  • Playgrounds & Schools
  • Public areas
  • Physical Hazards, trees, pylons, ditches, wind drift susceptibility, steep & unstable ground
  • Fly tipped/hazardous items
  • Consideration of fencing & signage to secure the area
  • Pets/customers
  • Access issues
  • TPO’s
  • Other non-target plants/foliage

The aim is to outline obvious factors needing due consideration and documentation.

Upon the completion of the risk assessment, biosecurity measures must also be outlined and put in place following the codes of best practise. Biosecurity is essential on all sites, at all times, to reduce the risk of spreading any invasive plant. Once the risk

assessment has been fully considered, and biosecurity measures have been put in place the next stage is to put forward a method statement. The method will include an explanation to the client of application procedures, an understanding of the products which will be recommended by the surveyor and the operating parameters which will have taken into account all elements of risk. Timing of application and weather considerations have to be outlined and equipment types best suited to the tasks are now also considered.

General Risk Assessment includes:

  • Do not use where bystanders will come into contact with spray.
  • Use only by staff with a relevant National Proficiency Tests Council spraying certificate.
  • Check equipment regularly for leaks.
  • Carry out a COSHH assessment before working.
  • Have spill kit available on site.
  • Do not use where water courses or water bodies (except with Environment Agency permission), non-target plants or sensitive areas, (e.g. play areas) will be affected by spray drift.
  • Use only by trained operatives.
  • Ensure pre-use checks are completed.
  • Ensure maintenance schedule is completed.
  • Use care when handling.
  • Wear personal protective equipment.
  • Follow chemical manufacturer’s directions.
  • Do not use near people – exclude people from the area of operation and warn people on neighbouring land of the planned use.
  • Have an emergency procedure in place for those who come into contact with the spray.#
  • Use correct lifting technique.
  • Place on waist high bench before lifting onto operator’s back
  • COSHH- Control of Substances Hazardous to Health

With the use of any hazardous chemicals, COSHH assessment sheets are also required as this concentrates on the hazards and risks associated to hazardous substances to the individual and to manage the exposure to hazardous substances to prevent ill health.

All our staff are fully trained with the relevant NTPC qualifications

  • PA1 Safe Handling & Application of Pesticides
  • PA6A Use of Hand Held Applicators on Land
  • PA 6AW Use of Hand Held Applicators on Land & Near Water

In addition, our staff have

  • CITB Site Safety Plus- Health & Safety Training
  • CITB Site Safety Plus- Site Safety Training
  • CSCS- Construction Skills Certification Scheme


ISO9001 & ISO14000

Knotweed Services are certified with the ISO9001 & ISO14000 accreditation.

ISO9001 – the international standard that specifies requirements for a quality management system (QMS). Organizations use the standard to demonstrate the ability to consistently provide products and services that meet customer and regulatory requirements.

ISO14001- is the international standard that specifies requirements for an effective environmental management system (EMS). It provides a framework that an organization can follow, rather than establishing environmental performance requirements.

Rhizome dormancy can be induced by incorrect herbicide application. Where dormancy exists the knotweed may look dead above ground (or may not even be visible) but the rhizome system in the ground remains alive ready to send up new shoots when the dormancy is broken.

A 5 year, in-situ, herbicide management plan is essentially a ‘control’ method which puts Japanese Knotweed into dormancy. As the rhizomes are not being removed from the soil, if the soil were to be disturbed, the Japanese Knotweed would become viable and start to grow again. Disturbing the ground could also fragment the rhizome system, leading to spread and regrowth of the Japanese Knotweed.

As above, if the Japanese knotweed is in dormancy we would strongly suggest you not to do this – if you are looking to redevelop/landscape or disturb the ground, complete removal (excavation) of the Japanese Knotweed is advised.

Knotweed Services will endeavor to keep disruption to a minimum, but inevitably some loss of enjoyment that the property and garden provides will be experienced. The amount and duration of disruption can depend on the treatment method adopted.

  • To minimise spread, if you cannot control access, fencing and warning signs should be used to prohibit unauthorized access into the affected area.
  • During application of herbicide, please keep persons and pets out of the area. The herbicides used are not harmful to mammals if used correctly, however unnecessary exposure should be avoided.
  • Do not allow the above ground knotweed vegetation to be trampled on, cut down or damaged. Damage to the above ground part of the plant makes the treatment using herbicide less effective. In certain circumstances it can also lead to further spread.
  • You should also notify all relevant parties with access to the infestation that the cutting down/pulling out of any Japanese Knotweed is not permitted during a treatment programme as to do so would severely hinder the control of the Japanese Knotweed, or worst case scenario cause new infestations to occur.
  • A 1m boundary should be left around the infestation to avoid contaminating surrounding soil.
  • It is imperative that no Japanese Knotweed is permitted to be disturbed, broken / pulled during an in situ control programme as this will delay control timescales and potentially increase control costs in the end.

Knotweed Services has a wealth of experience and success within the Japanese Knotweed Industry. We pride ourselves in the exemplary customer service, support, guidance, advice & services we provide from our experienced staff and this has been the driving force behind the success of our business, ensuring that customers are represented, protected and well-informed. Our services and processes are uncomplicated, thus ensuring our clients are confident in the knowledge that Knotweed Services (UK) Ltd will take full control and responsibility of burdensome Japanese Knotweed removal for you.

Whilst Knotweed Services (UK) Ltd is approaching it’s 6th year of trading, our experience and success with Japanese Knotweed, in both the residential and commercial sectors, goes way beyond that as we previously traded under our parent company- Arrow Services (Midlands) Ltd (A property maintenance company with an annual turnover of £3.3million, which has a long established trading history of 20 years) before making the decision to go solo as an independent, Specialist Japanese Knotweed Company. Both companies retain the same Managing Director to this day.

We have sucessfully helped 1000’s of domestic & commercial clients with the implementation of management plans for Japanese Knotweed which has also included helping clients navigate the buying & selling process of properties/development of land with JKW.

We have successfully dealt with 100’s of lenders and conveyancing professionals across the country and our promise to clients is that we will successfully manage & control Japanese Knotweed. We also have extensive experience and contracts with landlords, letting agents, property management companies, estate agents, Civil engineering companies, Construction companies, housing groups & conveyancing professionals to look after Japanese Knotweed and ultimately, safeguard their or their clients assets.

As an example, clients currently include:

Dixons, Robert Oulsnam & Company, GDC Group, Savills, Caldecotte Group, eigroup (formerally Enterprise Inns), Fine & Country, Andrew Grant, Oulsnam Lettings, Redrow, Wisemove, McCarthy & Stone.(this list is not exhaustive)


Are your pictures on a different device? Don’t have pictures available at the moment? No problem! Sending pictures to us is EASY at ANYTIME. You can contact us via the following:

SMS Text







Fill in the form below, attach your pictures and we’ll let you know if the plant in your picture is Japanese Knotweed.

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