What is Japanese Knotweed?

Japanese Knotweed is the most invasive plant known in Britain today. The plant originated in Japan where it thrives on disturbed ground. It was introduced to the UK in the early 19th Century as an ornamental plant also being used as a feed crop for cattle. The Victorian Horticulturalist who introduced the plant can not have envisaged the devastating impact Japanese Knotweed would have.It is effectively a giant herbaceous perennial which grows at an alarming rate of up to 10cm per day in any type of soil. It forms dense clumps of up to 3m (10ft) in height. Japanese Knotweed thrives on disturbance and spreads by natural means and by human activity. Very small fragments of rhizome (underground stems), as little as 0.7g - approximately the size of a fingernail - can produce fresh new plants. However, it is below ground where this invader causes the biggest problems, as each stand creates a rhizome network that can extend to 3m in depth and 7m in all directions. This makes it a serious threat to construction where it can have devastating consequences damaging foundations, drains and other underground services.

In Japan, Japanese Knotweed is controlled naturally by a combination of fungus and insects. However, in the UK, there are no natural enemies for Japanese Knotweed and it outcompetes all our native species for light, water and nutrients.
The speed at which Japanese Knotweed has spread throughout Britain has been nothing less than spectacular. The damage it has already caused to commercial and domestic sites is practically unquantifiable and it now occupies a site in every 10km of England and Wales and is also present to a lesser extent in Scotland, Ireland and other parts of Europe.
The aggressive growth pattern is capable of exposing weaknesses in hard engineered structures such as concrete, tarmac, brick walls and foundations.

Specific problems caused by Japanese Knotweed are:

• Damage to paving and tarmac areas
• Damage to retaining wall structures
• Damage to building foundations
• Damage to flood defence structures
• Damage to archaeological sites
• Reduction in land values
• Aesthetic issues
• Reduction in biodiversity through out-shading native vegetation
• Many insects/wildlife that are dependent on our native plants are lost or in danger
• Restriction of access to riverbanks for anglers, bank inspection and amenity use

The Law

Due to the destructive characteristics of Japanese Knotweed, strong legislation is in place to control the magnitude of the problem.

Five common legal issues with regards to Japanese Knotweed:

• You can be sued (under laws relating to private nuisance under common law) for costs and damages if you allow Japanese Knotweed to spread from your property onto that of an adjacent landowner.
• It is an offence to cause the spread of Japanese Knotweed under Section 14(2) of the Wildlife and Countryside Act 1981 (WCA 1981)
• Fine of £5,000 and/or 6 months imprisonment, or 2 years and/or an unlimited fine on indictment.
• The Environmental Protection Act (EPA) 1990, Duty of Care Regulations 1991 state that cut Japanese Knotweed material and soil containing rhizomes must be disposed of as controlled waste.
• It is not illegal to have it on your land
• It is not a notifiable weed

For a full description of all Japanese Knotweed legislation, please refer to the Environment Agency ‘Knotweed code of practice’ here.

How Can Geosphere Environmental Help?

First off, if you suspect or are concerned about invasive species such as Japanese Knotweed on or near to your land call us now for a survey immediately on 01603 298076.

Your next course of action is to discuss the issue with our specialists in person, we can take your site specific constraints and determine your best course of action to reliably keep projects within budget, and on schedule. We can also provide an information workshop on request or point you in the right direction for help and guidance on the issue.

The schemes we can undertake with you are flexible methods of eradication – we do not provide a miracle one season cure that may (or may not) work, or warrantees caveated beyond practicality. What we offer is a solid base of experience in dealing with these issues at competitive rates – we can cut through the scare mongering that preys on those affected Japanese Knotweed and can assure you that the best course of action is clear and achievable.

The most important aspect is not to delay, the sooner the issue is identified and dealt with the lower the overall cost.

For those requiring specifics – we operate all over the UK. Our specialists are NPTC certified, CSCS certified, environmentally aware and are health and safety trained. All of our operatives have extensive experience of dealing with invasive species on developments, private properties, secure sites, airfields and in close proximity to watercourses.

The herbicides and methods we use are all certified by the Environment Agency and we adhere to the Code of Practice publications.

We are 100% confident you can save time and money using the services of Geosphere Environmental Limited; please feel free to ask us to match any prices for your invasive species eradication.