Treatment Options

Japanese Knotweed is now one of the most problematic invasive alien species across Ireland and is a major management concern for public authorities. It is an increasingly common sight on waste ground, riverbanks and roads and is classified as one of the top 100 worst invasive species worldwide.

Japanese Knotweed has aggressively invaded natural habitats outcompeting native plants, forming tall dense stands that can grow to 2-3 metres, excluding all other vegetation. Indigenous plants cannot compete with this invasive plant and local biodiversity is reduced and endangered.


Japanese Knotweed Solutions

Japanese Knotweed can also seriously damage buildings and infrastructure, it has the ability to weaken concrete, tarmacadam and other hard standings if any weaknesses exist.

When Japanese Knotweed takes over riverbanks, it can damage flood defence structures and undermine the ability of channels to carry flood water.

The Japanese Knotweed Company offer specific packages to suit all client’s needs. Whether the infestation is large or small, residential or commercial, we offer a wide range of Japanese Knotweed solutions and eradication options.

It is our experience that there is no one size fits all when determining a Japanese Knotweed eradication strategy as no two infestations are the same, we use a number of different treatment methods or in some cases a combination of a number of methods depending on the location of the site, the age of the infestation and other site-specific pressures with regards to timescales, costs and ecological issues.

Japanese Knotweed Solutions in Ireland

Treatment Methods

Herbicide Treatment Programme:

A herbicide treatment programme can provide a cheap, effective and simple solution to treating a Japanese Knotweed infestation, herbicide treatment can be administered by foliar spray, stem injection or by a weed wipe methodology.
The use of any herbicide treatments and the means by which they are administered will be site specific, determined by initial site survey and onsite factors, and all relevant regulations will apply as standard.

Japanese Knotweed Solutions - Herbicide Spraying Programme

Above Ground Bunded Method:

This bunded method can be used on a site where a parcel of land can be allocated to accept soils affected with Japanese Knotweed rhizome root material. A geotextile membrane will be placed to protect the underlying ground where the bund is to be created, it is recommended that the bunds are no deeper than 600mm. All regrowth at these bunds will be controlled and managed using a bespoke herbicide treatment programme. The soils at these bunds will be classified as controlled soils and cannot be removed from site without a transport & removal licence from the National Parks & Wildlife Services being raised.

Japanese Knotweed Solutions - Bunded Method

Onsite Deep Burial:

The deep onsite burial of affected soils within a geotextile capsule could also be considered as a treatment option. It is recommended that deep onsite burial only take place beneath green areas where no future ground disturbance will occur. This option is again site specific and the site would have to undergo ground investigations in order for suitability to be determined.

Japanese Knotweed Solutions - Excavation followed by sifting & burial

Off Site Removal:

Off-site removal allows for the complete eradication of the affected soils from site, this option requires a removal and transportation licence to be obtained from the National Parks & Wildlife Services. The Japanese Knotweed Company are experienced in raising all relevant permits and licences for this option.

Japanese Knotweed Solutions - Removal to landfill

Insertion of geotextile membrane:

Using a geo textile membrane the Japanese Knotweed company will create a non –permeable barrier between a building or structure to ensure the containment of the infestation thereby controlling the issue for treatment. This method can be particularly useful for people with boundary disputes of troublesome neighbours as well assisting planning applications.

Japanese Knotweed is a difficult plant to control due to its extensive underground rhizome system and treatment options are both dependent on and recommended on site specific factors.


For more information on our services available.