Japanese Knotweed, an invasive plant native to Japan, has rapidly spread throughout the UK, causing environmental, economic, and social problems. As a challenging weed to control, its relentless growth often leads to the destruction of infrastructure, reduction in property values, and threats to biodiversity. To raise awareness of this issue and provide effective solutions, it’s vital that a thorough Japanese Knotweed survey is conducted.

In our experience, we have found that the first step in tackling this invasive species is understanding its characteristics, distribution, and impact within the affected area. Equipped with this valuable information from a detailed survey, we can establish a targeted and strategic approach to control or eradicate the plant.

A comprehensive Japanese Knotweed survey not only identifies the extent of the infestation but also uncovers potential risks and hidden damages caused by its invasive nature. 

If you suspect Japanese Knotweed may be on your land or in close proximity to your land or what peace of mind there is no Japanese Knotweed, we can assist with a full boundary survey. As a fully accredited PCA contractor, we provide in depth Japanese Knotweed surveys for residential home owners, commercial business and developers.

Our Japanese Knotweed Surveys will accurately identify your infestation, condition and its size. We are approved by RICS (The Royal Institute of Chartered Surveyors) to undertake and complete these surveys as members of The Property Care Assocition (PCA). All our Japanese knotweed surveys are conducted by one of our in house certified surveyors of Japanese Knotweed (CSJK) qualified surveyors.

Our detailed Japanese Knotweed Surveys will provide :

Japanese knotweed survey costs

The price of our Japanese Knotweed surveys start at a cost of £125 plus VAT and may increase or vary depending on certain situations such as the size of land we are required to survey, location of the survey and several other factors such as access to the infested areas. If a customer proceeds with a management plan following a survey we deduct the cost of the survey from the cost of the management plan which means the survey is in effect completed free of charge.

Residential Surveys

If you wish to buy or sell a property, and you suspect Japanese knotweed is present, a survey undertaken by a PCA qualified specialist anda  subsequent management plan may be required to satisfy mortgage lenders and home buyers and sellers.

Commercial & Development Surveys

When it comes to construction projects, a Japanese knotweed survey is best undertaken before any work begins to assess the land proposed for development, and ideally an invasive weed survey is carried out during the purchase process or following the ecology site reports.

Japanese knotweed may cause delays to construction projects if not identified prior to development. We will carry out full site surveys to establish if there is any problems or risks, assess the problem against any proposed development plans. We will issue remediation options and costs which are most suitable to the site development plans.

Conducting a Japanese Knotweed Survey

Knotweed eSurvey Process

Conducting a Japanese Knotweed Survey involves several key steps. First, we must identify the presence of Japanese Knotweed on the property. Our team are well-trained in recognising the plant throughout the year, even if it has retreated underground during the winter months.

Site visits are required to examine the extent and severity of the infestation. We can typically complete a visit efficiently, with minimal disruption to the property owner. Our surveyors will inspect the entire property and its boundaries, taking photos and recording relevant data.

During the survey process, we consider the following:

• The plant’s location, distribution, and density
• Evidence of previous treatments, if any
• Risks associated with the infestation, such as structural damage or hindrance to construction projects

Interpreting Survey Results

Post inspection, we compile a detailed Survey Report to convey our findings. This report may include:

1. Extent of Infestation: Indicator of scale and spread of the Japanese Knotweed on the property
2. Severity: Categorised on a scale ranging from low (a few isolated shoots) to high (dense growth)
3. Site Maps: To help visualise the precise locations of the Knotweed on the property
4. Photographic Evidence: To support our findings and demonstrate the plant’s appearance

Post-Survey Actions

Upon reviewing the survey results, it is critical to develop a Knotweed Management Plan tailored to the specific infestation. This plan typically outlines:

• Treatment methods: such as chemical treatment, excavation, or root barriers
• Duration and frequency of treatments
• Management and monitoring of the infestation
• Estimates of costs and potential disruption to the property owner

Our team will make sure treatments are suitable and supported by a 10 years Insurance Backed Guarantee. This guarantee protects the property owner in case future treatments and remediation are required after completing the initial management plan.

A Japanese Knotweed Survey is a thorough process, designed to identify, document, and manage any infestation on a property effectively. With the assistance of our knowledgeable surveyors, treatment plans can be developed and implemented with confidence, ensuring a favourable outcome for all involved parties.

Japanese Knotweed Management Plan

If you proceed with our proposed Knotweed Management Plan, our experienced technicians will visit the property as per the knotweed management to commence treatment / removal. This will be delivered within the optimal timelines, where our experts will carry out specialist treatment or removal methods to guarantee an effective solution.

Understanding Japanese Knotweed

Identification and Characteristics

Japanese Knotweed (Fallopia japonica) is an invasive plant species native to Japan, China, and Korea. As a robust, fast-growing perennial, it can quickly establish itself and spread across a wide range of environments. The distinctive characteristics of Japanese Knotweed make it relatively easy to recognise:

• Stems: Resemble bamboo, with a hollow structure and reddish-brown markings.
• Leaves: Heart or spade-shaped, approximately 12-14 cm long and 9-12 cm wide.
• Flowers: Small, creamy-white flowers that typically bloom between July and October.
• Roots: An extensive network of rhizomes, potentially reaching up to 3m in depth and 7m in length.

In addition to these visible signs, Japanese Knotweed can also be identified by expert surveyors through more subtle indicators, such as leaf arrangement patterns and growth habits.

Spread and Infestation Patterns

Japanese Knotweed spreads primarily through its vigorous rhizome system, but it can also disperse through fragments of stems, leaves and roots. This invasive species is notorious for its ability to grow through concrete, tarmac, and even building foundations, causing significant damage to structures and other natural habitats in the process.

When dealing with infestations, it is crucial to understand the potential spread patterns and locations, as well as the implications on the surrounding land. Some of the most common causes of spread include:

To effectively manage and eradicate Japanese Knotweed, organisations such as Natural England provide recommendations and guidelines for landowners and developers. These may involve herbicide treatment, excavation and removal, or a combination of these methods, ensuring the invasive plant species is responsibly controlled and managed.

Implications of Japanese Knotweed on Property

Japanese Knotweed is an invasive plant that can cause significant problems for homeowners, property owners, and buyers. In this section, we will discuss the implications of Japanese Knotweed on property, covering its effects on property value and sale, mortgage and insurance considerations, and legal and environmental obligations.

Effects on Property Value and Sale

Japanese Knotweed can cause structural damage to buildings and other structures by growing through foundations, walls, and drainage systems. This can negatively impact the property’s overall condition, and, as a result, the property value.

According to the Royal Institution of Chartered Surveyors (RICS), the presence of Knotweed can lead to a property decrease in value by up to 5% – 20%.

When selling or buying property, Japanese Knotweed can have a substantial influence on the process. Solicitors and estate agents require disclosure of the plant’s presence, and potential buyers may be deterred from purchasing, leading to a longer time on the market for a property.

Mortgage and Insurance Considerations

The presence of Japanese Knotweed can also affect mortgage and insurance considerations for homeowners and buyers. Many mortgage lenders are hesitant to provide loans for properties with Knotweed, due to the risk of damage and devaluation. In some cases, mortgage lenders require treatment plans with an insurance-backed guarantee (IBG) before approving loans.

Regarding property insurance, Knotweed-infested properties may incur higher premiums, or some insurers may decline coverage altogether. It is essential for homeowners and buyers to discuss these matters with their insurance providers, mortgage lenders, and solicitors to ensure they understand the risks and potential costs.

Legal and Environmental Obligations

Property owners have legal and environmental obligations concerning Japanese Knotweed. Under UK law, it is an offence to allow the plant to spread into the wild or to negligently dispose of it. The plant must be considered as controlled waste, and proper disposal methods should be followed, according to the Environment Agency’s guidelines.

If the presence of Knotweed causes damage to a neighbouring property, the homeowner can face legal claims from neighbours. Failure to control the plant can also result in fines and legal action from environmental authorities.

To adequately manage and control Japanese Knotweed, it is crucial to work with professional treatment providers and follow RICS guidelines. This can minimise the potential negative implications for property owners, sellers, and buyers alike.