Invasive Weeds

Our careful procedures ensure correct identification and effective control of invasive species, including Japanese Knotweed.

ERS is experienced in the identification and remediation of sites colonised by invasive plant species and can provide solutions for effective and economical treatment.  Control and eradication programmes are designed to meet client and site requirements.

If you suspect you may have a problem with invasive weeds, ERS can help with survey and plant identification and will develop a control and eradication programme tailored for your site.

Japanese Knotweed (Fallopia japonica)

Japanese knotweed is an ornamental garden plant which was imported to the UK in the mid 1800s. It can quickly grow to form stands over three metres in height with a complex underground root network.  At the end of the growing season the stems die back but the underground rhizomes are still very much alive and therefore spread is often unintentional.

Japanese knotweed can penetrate pavements, roads and car parks and can cause structural damage to walls, foundations, drainage works and flood defence systems.

It is essential that it should be properly controlled where new development is taking place and it is an offence under the Wildlife and Countryside Act 1981 to knowingly grow or allow Japanese knotweed to spread.

Giant Hogweed (Heracleum mantegazzianum)

Giant hogweed is now found in many areas of wasteland and riverbanks. It measures up to six metres in height and forms dense colonies that suppress the growth of native plants and grasses, leaving the banks bare of vegetation in winter.

This plant is highly dangerous to humans; the stems and leaves bear small hairs containing poisonous sap and the slightest touch or brush past causes painful blistering and severe skin irritation.  This may persist for years and cannot be exposed to sunlight.

Rhododendron (Rhododendron spp.)

Rhododendron species and hybrids have spread rapidly through many parts of the UK to colonise acid heathland and woodland environments.  Although cultivated for its attractive blooms, the plant forms dense stands which shade out native species, threatening local ecosystems.

The removal of rhododendron can help a whole range of species and Scottish Natural Heritage has included Rhododendron ponticum in the five year Species Action Framework strategy for priority species management in Scotland.

Rhodedendron can be very difficult to control and eradicate from an area, requiring sustained and well-timed efforts.  ERS works with landowners to develop appropriate and effective eradication strategies.

Himalayan Balsam (Impatiens glandulifera) 

Himalayan balsam is often considered a beautiful plant, with its towering stature, translucent stems and crimson, purple or white flowers that emerge from June to October. 

It is however a highly invasive alien species that favours shady and riparian habitats and can propagate rapidly, causing significant ecological damage. 

Himalayan balsam is increasingly the subject of control measures and is proposed for inclusion under Schedule 9 of the Wildlife and Countryside Act 1981.

Ragwort (Senecio jacobaea)

Ragwort is a native species of Britain, recognised in the flower stage by the rosette of yellow daisy like flowers. It is usually found on roadside verges, railway tracks, wasteland and pastures.

Ragwort is dangerous to livestock and other wet-nosed animals and frequently requires management, particularly in agricultural settings. The Weeds Act 1959 provides for the control of the spread of ragwort.