Commercial

Conservation Land Services Limited are specialists in the control of Japanese Knotweed within the commercial property environment and have extensive experience in the treatment of both green and brownfield sites, across every stage of development. The specific demands of your work are paramount and we are confident that, by engaging Conservation Land Services Limited, our clients are minimising the impact Japanese Knotweed will have on the scope, budget and timing of any project.

factories-kntweed


Why choose Conservation Land Services Limited?

Early engagement: Time is of the essence. Wherever Knotweed is involved, any hesitancy means a bigger problem, higher costs and more project delays. Conservation Land Services endeavour to have a PCA certificated surveyor on site within 24 hours.

Site mapping: We will provide clients with a CAD generated site map, showing exactly where the Knotweed is located. Our GPS mapping system is up to ten times more accurate than some industry equipment, plotting site locations to within 30cm accuracy.

Purchase decision: Conservation Land Services offer a pre-purchase risk assessment for all invasive weeds and are available to support you in any future purchase decision.

Post treatment: We advise and support the client in producing a re-vegetation programme that is best fit with the setting and local environment of the development. In addition to this, where requested, we are able to offer expert advice on how to maximise the biodiversity value of the area. This includes advice on practical biosecurity measures to minimise any further invasive weed infestation on the site.

Ongoing support: We can provide a level of education to site personnel and management about Japanese Knotweed and other invasive weeds. Our seminars have proven advantageous for clients in the past, equipping site managers with specific knowledge to help avoid unnecessary expensive errors. Examples include provision of fact sheets and telephone support.

Japanese Knotweed control options

Herbicide Options

Herbicide application by foliar spray

(3-5 growing seasons)

When foliar application is possible, it is the most cost effective method for the control of Japanese Knotweed material and being carried out on site removes the risk of spreading the plant further. Typically, control of Japanese Knotweed with herbicide treatment can be achieved within three growing seasons, although long established infestations may require further treatment.

This is not a suitable technique if there are plans for development which would result in disturbance of the ground within the treatment area.

Herbicide application by stem injection

(3-5 growing seasons)

Stem injection is an appropriate technique where there are limitations to the use of foliar application, such as proximity to water or surrounding vegetation that must be protected. Again, this is a cost effective technique, however, as with foliar application, it is only suitable if there are no future development plans which would disturb the area concerned.

Excavation Options

Whilst the PCA code of practice advises that, wherever possible, Japanese Knotweed should be treated in its original location, development plans often mean that the infested area will need to be disturbed and this means that in situ herbicide treatments are not suitable. Instead, in order to protect project milestones, the Japanese Knotweed rhizome material can be excavated.

hand-glove-small-knotweed-01

“a piece as small as a fingernail
has the potential to lead
to another infestation”

excavation-01

Keeping in mind that just 0.7g (a piece as small as a fingernail) has the potential to lead to another infestation, we draw upon our expert knowledge and years of experience to accurately trace the knotweed root system, thereby ensuring that the amount of spoil removed is kept to a minimum.

There are several variations on this technique, the choice of which will depend on the site itself and future plans for development.

Bunding

Where local conditions mean that burying the Japanese Knotweed is not possible, a Japanese Knotweed bund can be created. A bund is a shallow area of Japanese Knotweed contaminated soil, used to “buy time” for the herbicide treatment of the knotweed that would not be possible in its original location.

This method is best suited to larger sites with an area of land that can be left untouched whilst the “quarantined knotweed” is treated.

Excavation and On-Site Burial

One technique is to excavate and bury the rhizome material in another on-site location. The contaminated material needs to be buried at least 5m deep, however, by using root barrier membrane containment we are able to reduce this requirement to between 2-3m. Where this technique is used, we co-ordinate with the Environment Agency to ensure appropriate approval is in place.

Using our accurate GPS mapping, we ensure that all relevant parties have a record of the exact location of the buried cell, thereby avoiding any accidental disturbance of the area.

“Dig and dump”

Excavation of Japanese Knotweed material, which is then transported to a licensed landfill site, is an immediate solution to Japanese Knotweed control. However, it is often the most expensive option due to high costs related to landfill disposal. This technique needs very careful planning with regard to the agreement of haulage routes in and out of site, as well as the excavation itself, because throughout the complete process, just 0.7g of missed or dropped rhizome material is viable to cause further infestation.Dig and dump

This method can be used in conjunction with soil screening, which we would use to further reduce the amount of soil removed from the site.

Incineration

We will often use the controlled burning of the stem, rhizome and crown material as part of the treatment programme for Japanese Knotweed infestations. Burning greatly reduces the amount of material to bury or take to landfill, but is subject to local planning conditions and/or conditions of the site.

+ Bunding

Bunding

Where local conditions mean that burying the Japanese Knotweed is not possible, a Japanese Knotweed bund can be created. A bund is a shallow area of Japanese Knotweed contaminated soil, used to “buy time” for the herbicide treatment of the knotweed that would not be possible in its original location.

This method is best suited to larger sites with an area of land that can be left untouched whilst the “quarantined knotweed” is treated.

+ Excavation and On-Site Burial

Excavation and On-Site Burial

One technique is to excavate and bury the rhizome material in another on-site location. The contaminated material needs to be buried at least 5m deep, however, by using root barrier membrane containment we are able to reduce this requirement to between 2-3m. Where this technique is used, we co-ordinate with the Environment Agency to ensure appropriate approval is in place.

Using our accurate GPS mapping, we ensure that all relevant parties have a record of the exact location of the buried cell, thereby avoiding any accidental disturbance of the area.

+ “Dig and dump”

“Dig and dump”

Excavation of Japanese Knotweed material, which is then transported to a licensed landfill site, is an immediate solution to Japanese Knotweed control. However, it is often the most expensive option due to high costs related to landfill disposal. This technique needs very careful planning with regard to the agreement of haulage routes in and out of site, as well as the excavation itself, because throughout the complete process, just 0.7g of missed or dropped rhizome material is viable to cause further infestation.Dig and dump

This method can be used in conjunction with soil screening, which we would use to further reduce the amount of soil removed from the site.

+ Incineration

Incineration

We will often use the controlled burning of the stem, rhizome and crown material as part of the treatment programme for Japanese Knotweed infestations. Burning greatly reduces the amount of material to bury or take to landfill, but is subject to local planning conditions and/or conditions of the site.

Treatment completion

Control is only deemed complete when there have been two full growing seasons of monitoring with no evidence of Japanese Knotweed growth. At this point,  Conservation Land Services Limited will provide a certificate of completion.