Japanese Knotweed

Japanese Knotweed (Fallopia Japonica) and Invasive Species

Parklawn Tree Services are experienced and knowledgeable in the management and treatment of Japanese Knotweed as well as a variety of other invasive species such as Himalayan Balsalm (Impatiens glandulifera), Winter Heliotrope (Petasites fragrans), Giant Hogweed (Heracleum mantegazzianum), and Buddleia (Buddleja globosa) , having successfully completed a number of treatment programs for public bodies and state agencies including Irish Rail and several Local Authorities.

Japanese Knotweed is a perennial, which dies back to ground level during the winter, re-growing from rhizomes (roots) as shoots during the spring and summer. It was introduced to the British Isles during the 1800s as an ornamental plant, but due to its aggressive growth, propagation properties and lack of native competition, it can spread uncontrollably, having a detrimental effect on native low shrubs and plants as they struggle to compete for light and space. As native plant species are also the preferred food source for indigenous insect and animal populations, the knock-on effect to the local ecology is potentially devastating. For this reason Japanese Knotweed has been classified as an invasive species.

In addition to this, its ability to establish in virtually any nook or cranny makes it particularly problematic for buildings and man-made structures, often growing in the cracks of stone, or concrete compromising their structural integrity and causing potentially severe damage requiring expensive repairs.

Identifying Japanese Knotweed

Japanese Knotweed has an appearance which is very similar to Bamboo. It produces straight hollow stems or canes up to 7ft in height, with branches growing from the nodes along the length. The stems are brown or reddish-brown in spring/summer sometimes with noticeable purple flecks. Its leaves are rounded and triangular up to 14cm (5½in) across.

During the winter the stems die off to ground level, leaving light brown dried out or broken hollow stems, from which the shoots re-sprout in the spring.

What to do if you discover Japanese Knotweed on your property

If you identify Japanese Knotweed, it is important that it is managed correctly to prevent the further spread and to facilitate the effective eradication of the species. The National strategy has been ineffective thus far and the species continues to spread at an alarming rate. The species propagates from even the smallest pieces of plant matter, in particular the rhizomes. For this reason, no part of the plant should be included in regular green waste.

Parklawn Tree Services have the knowledge and experience to implement an effective treatment program, which will include several strategically timed site revisits and further treatments to ensure the complete removal while preventing the further spread of this ecologically destructive and stubborn plant.