Sunday, 20 July 2008
Japanese Knotweed (Fallopia japonica) is a perennial plant brought into the UK as an ornamental garden plant in the 1800’s. It is the most invasive plant/weed in Britain.
Japanese Knotweed is listed under Schedule 9, Section 14 of the Wildlife and Countryside Act 1981. It is an offence under this act to plant or otherwise cause the species to grow in the wild. Allowing Japanese Knotweed to grow over the boundary of your property can be classed as allowing the species to grow in the wild and would be an offence under the Act and leave you to be liable to prosecution. Failure to control this species may result in enforcement action by the Environment Agency.
Japanese Knotweed is a weed problem that can be successfully treated with herbicides, although it may take several applications to eradicate this weed.
Japanese Knotweed grows in the form of a bamboo like stem with green oval shaped leaves with a distinctive zig zag pattern, in early spring shoots will grow from the stem which will be red or purple in colour.
These stems grow at a great speed, reaching a height of 1.5 metres by May and 3 metres by June. In late summer to early autumn flowers will appear on the stems, which will be creamy-white and will grow in clusters.
The stems will die down in late autumn to early winter, when they will turn a dark brown and the leaves and flowers will be shed. The dead stems can remain for up to three years before decomposing.
Japanese Knotweed is spread easily by rhizomes (parts of the root) and a piece as small as 0.8grams is all that is needed to allow the plant to spread. The plant commonly grows during transportation, or by being mowed or flailed as this causes particles to blow around. Japanese Knotweed will grow wherever it lands, it has even been known to grow through floorboards and into living rooms!
DO NOT waste time. If you have Japanese Knotweed on your property, treat it immediately. Do not allow it to become established.
DO NOT fly-tip Japanese Knotweed, or any other garden waste.
DO NOT include with normal household waste.
DO NOT contaminate green waste bins with knotweed material.
DO NOT compost knotweed.
DO NOT flail, mow or cut Japanese Knotweed, as this will cause it to spread. Flailing of the dead stems after herbicide treatment and complete dieback or in the winter period this is acceptable. The plant is herbaceous meaning that the aerial parts of the weed will be killed off in the winter by frosts.
DO NOT spread Japanese Knotweed stems and crowns. All material removed must be safely contained and disposed of at a licensed disposal site. The landfill operator must be notified that you are disposing of Japanese Knotweed, as the waste must be buried at a depth of at least five metres to prevent re growth.
DO NOT spread soil contaminated with Japanese Knotweed rhizomes (root system). Any soil that is obtained from ground within seven metres of a plant could contain rhizomes. The rhizome is highly regenerative and will readily grow into new plants.
DO NOT chip or shred Japanese Knotweed material. Mechanical chippers do not kill Japanese Knotweed. If you spread any chipped or shredded material Japanese Knotweed can re grow from minute pieces of the plant.
Under the Wildlife and Countryside Act, 1981 it is an offence if you cause Japanese Knotweed to spread. Simply allowing the plant to grow from your property into a neighbours garden could be classed as an offence. The use of a tractor flail will also assist in the spread of the plants and this will also be an offence.
Contact Customer Services Tel: 01302 736000 for advice, and they can arrange for someone to remove it for you, please telephone for details and costs.
There are several herbicides available for use on Japanese Knotweed, and the choice of herbicide will be dictated by the situation the weed is growing in.
TORDON 22K – Picloram
This product acts through foliage and the roots, has a residual activity for up to two years and does not kill grasses. The disadvantage with this product is that it cannot be used near watercourses or under tress that you wish to retain, as it can be absorbed into the root system and will kill mature trees.
ROUNDUP Pro Biactive/Pro green – Glyphosate
This acts through the foliage and is trans-located through the root system. This product will kill all vegetation including grasses, and has the added benefit that it can be applied in or near watercourses. The product cannot be absorbed via root systems and it is broken down on contact with soil. Depending on the time of the first application you may need to spray two to three times to ensure a good kill.
GARLON/TIMBREL – Tryclopyr
This is a selective herbicide, rapidly absorbed through foliage and roots. Grasses not affected at normal dosage rates. Again, the use of these products is not permitted near watercourses.
It is essential that you comply with the recommendations on the product labels. If you have any concerns over the use of these products please contact Customer Services: 01302 736000.
The Environment Agency have some further information about Knotweed, you can access their site by following this link; www.environment-agency.gov.uk
