Japanese Knotweed Treatment and Removal in South Wales

Do you have, or do you think you have Japanese Knotweed? This can cause a lot of stress and worry. Don’t despair! Green Leaf Remediation offer services throughout South Wales for the identification, treatment and if necessary the removal of knotweed. If you would like advice or to request a visit please telephone  on 01269 591651

Knotweed (Fallopia Japonica) – What is Knotweed?

Knotweed is an invasive weed that is a plant from the dock family and it typically has sheaths where the leaves join the stems.

Japanese Knotweed is a highly invasive plant that will grow rapidly, overtaking other vegetation around it left to its own devices. Knotweed is very difficult to remove and its existence on or close to a property could have an impact on property sales, purchases and lead to unforeseen costs.

Knotweed has a really wide and incredibly strong root system. The roots can grow up to 3m in down in the soil and 7m wide and upwards. It grows very rapidly, at a rate of more than a metre a week. The roots can impact existing structures and make it difficult to build foundations and incorporate drain systems into the ground however it does not grow through solid concrete.

It is extremely difficult to eliminate 100% of the roots effectively and if a tiny piece of its grass root is not fully removed, it will rapidly regrow and spread.

Knotweed is known to target weak points, such as cracks in masonry, and can be persistent in growing through them if not removed.

Where did Japanese Knotweeds come from?

A Dutch doctor called Phillipe von Siebold came to the UK in the late 1840s and began to sell Japanese Knotweed to botanical gardens and high society figures.

The History Knotweed

By 1869 it became available for general sale in the UK and farmers began to use it as feed for their animals. By the late 19th century gardeners encouraged people to buy and plant knotweed in their gardens to bring a touch of greenery. Little did they know the devastating effects knotweed could have from their rapid growth and roots.

The effect of it being widely introduced a home or public gardens resulted in it spreading quickly and growing in the wild. By the 1930s the effects and impact of knotweed began to be realised and its reputation for being a lovely evergreen plant quickly diminished. Its invasive nature, roots and ability to spread and establish quickly were starting to show.

In Winter knotweed dies back to ground level but in early summer the bamboo-like stems emerge from rhizomes deep underground to shoot to over 7ft tall, whilst suppressing all other plant growth under and over the ground.

The Wildlife and Country Act made it an offence to introduce Japanese Knotweed into wild spaces in 1981 and by 1998 a survey showed that the weed-covered a huge area of 99 hectares in the Swansea area alone.

In 2011 aphids were released in Swansea to try and kill the widespread knotweed however it didn’t have the effect that was needed. An aphid is a small bug that feeds by sucking sap from plants; a blackfly or greenfly. Aphids reproduce rapidly, sometimes producing live young without mating, and large numbers can cause extensive damage to everyday homegrown and wild plants.

Since this time, the government is still at a loss for a way to properly control knotweed in the UK, so there are now companies that specialise in the removal of knotweed.

Are there any health benefits of Knotweed?

Some people believe there are some health benefits from Japanese knotweed, including; its ability to prevent and treat cognitive disorders, improve heart health, lower your risk of cancer, reduce gastrointestinal distress, lower blood pressure, maintain proper insulin levels, and many others.

Can you get a mortgage on a property with Knotweed?

It’s not impossible to get a mortgage on a property with knotweed, however, lenders are always very cautious due to its ability to spread quickly. In addition to this buyers and lenders are understandably wary when considering purchasing a property or land where knotweed is present. However, with a 5-year treatment plan in place, backed by a 10-year guarantee, we can help you or your buyer secure a mortgage.

Home Insurance and Cross-Boundary Issues

Insurance for a property with knotweed can also be very problematic.

Most buildings insurance policies do not cover you for damage caused by knotweed. If your neighbour has knotweed and your house is affected by it, most insurers are likely to pursue others for the cost of the damage caused to your property.

The hapless plight of homeowners experiencing difficulties in selling their property, due to a knotweed infestation on adjacent land has become increasingly prevalent in recent years and it ordinarily falls within the realms of risk category 3 or 4. It can become an awkward situation and has been the source of acrimonious and prolonged neighbourhood disputes.

Whilst there is legislation that can be pursued to induce the landowner where the infestation lies, into arranging remedial work, in truth the legislation is rather weak and certainly wasn’t unveiled by the UK government with the issue of Japanese Knotweed at the forefront.

In summary, we advise you to be extremely cautious if you are considering buying property or land where knotweed is identified. Costs to remove knotweed can escalate and full removal is not always guaranteed due to its ability to spread from one tiny root and its rapid growth.

Knotweed Myths, Misconceptions and Facts

There are many myths about how you can eradicate Japanese Knotweed and what the best course of action to take is. Pouring salt, diesel, caustic soda, turpentine, fairy liquid on the plant or into the ground are just some of the common fallacies which seem to have gathered momentum over the years.

The following statements are NOT true:

• “It will grow through solid concrete”
• “It can destabilise foundations”
• “It has the potential to cause structural damage”
• “Knotweed can damage buildings especially if left to grow unhindered for a number of years”
• “This invasive plant can have such a dramatic effect on structures, foundations & concrete”

In simple terms, if groundwork and construction work has been completed to a sufficient standard previously, then knotweed will not grow ‘through solid concrete’, it will not destabilise solid foundations, it will not cause structural damage, it will not ‘damage buildings’ and it won’t have a dramatic effect on any ‘solid structure’. These claims are misleading and in some cases, false.

The real truth about knotweed is that is a wild plant and it grows and spreads very quickly overtaking other vegetation around it.

About South Wales Knotweed

We are a local family-run, Invasive Weed Management company, offering a professional and reliable service. We launched in 2013 by Carwyn Templeton, a fully qualified Japanese Knotweed Certificated Surveyor (JKCS) through the Property Care Association.

We primarily specialise in eradicating Japanese Knotweed (Fallopia Japonica), along with other invasive plant species and ‘general nuisance weeds’ found in the UK. We offer our services for residential premises and land earmarked for housing and commercial development.

Knotweed Legislation

There is lots of legislation covering the handling and disposal of Japanese Knotweed and we are experts in this area, always offering you advice on the best solution for your property or land.

Our knotweed treatment methods are endorsed by the Environment Agency Codes of Practice and the industry trade body / The Property Care Association which can be tailored to suit you as the client.

Our Knotweed Control and Removal Methods

There are many ways to control and remove knotweed and you should always use a specialist and qualified company who fully understand the mind-field of legislation and techniques that should be used.

Knotweed Stem-Injection

Stem-injection is a low impact method of removing knotweed. It is normally used for smaller infestations and is used when the knotweed has established itself amongst other plants that you don’t want to be removed as there is less risk of damaging the surrounding vegetation. It can also be used in areas where there is a watercourse due to it being a less risky method of removal. The stem-injection process can be carried out in dry or inclement weather conditions and the soil need to remain undisturbed following the treatment.

Knotweed Foliar Application

Foliar Application is a spray method of knotweed removal and is used when the treatment can be repeated over several of its growing seasons. The knotweed is sprayed with an approved herbicide and the process is conducted 2 to 3 times in the first year depending on the size of the knotweed and then once in the following year. The process needs to be done in dry weather and the soil undisturbed in subsequent years.

Knotweed Weed Wiping

The Weed wiping method can be done in areas where there are other plants that you don’t want to be impacted, much like the Stem-injection method. The knotweed leaves are wiped with a sponge soaked with a suitable herbicide meaning only they are impacted.

Knotweed Bund / Stockpiling

Bund or stockpiling is a combined treatment of stem-injection or foliar application which is followed by excavation of the underground material and removal of the soil to a different section of the site. The new shoots that emerge are then subjected to further herbicide application. This method of removal is quicker than the more commonly used methods which are repeated annually and when done correctly it allows a developer to start using the land more quickly.

Knotweed Cell Burial / Root Barrier

Cell Burial or utilising a Root Barrier will avert the substantial costs of transporting the knotweed soil and waste to landfill, however, the site needs to be big enough for the knotweed material to be buried to a minimum depth or, if encapsulated within a geomembrane, it can be buried closer to the surface. Root barriers can be installed both vertically and horizontally and this method is used when there is a risk of cross-boundary contamination.

Knotweed Excavation & Removal Off-Site

Excavation & Removal of knotweed material off-site is a legitimate and swift control option. It has its advantages for development sites when done correctly, however, the significant logistical challenges of this method are challenging. There is a high risk of the knotweed spreading and therefore results in the secure movement of the material to landfill being costly. There is a considerable duty of care required under the Environmental Protection Act (EPA) 1990 with this method of removal. We are happy to act in a consultancy role as clerk of the works for this method of removal, providing certain conditions are met with the landowner or developer. We always advise that the Excavation & Removal method should only be used as an absolute last resort.

All of these treatment and removal services are provided to homes, businesses and properties. We will consider a staggered payment schedule for any work that does not involve a 3rd party, and for customers who require evidence of pre-payment in full from the outset from their mortgage lenders.

To find out more or if you have any questions about knotweed removal in South Wales, give us a call on 01269 591651 and one of our expert team will be happy to help.