Environmental guidance for your business in Northern Ireland & Scotland
You are responsible for the plants on your property and must ensure that you control their spread according to legislation and avoid damage to neighbouring properties.
Non-native plants are those species that have been brought into the UK. There are hundreds of non-native plants in the UK. Your business may come into contact with some of the most invasive ones, such as Japanese knotweed, giant hogweed and Himalayan balsam. Invasive non-native plants can cause problems for native species and reduce biodiversity (the variety of living organisms). Invasive non-native species are now widely recognised as the second biggest threat to biodiversity worldwide. Japanese knotweed can block footpaths and damage concrete, tarmac, flood defenses and the stability of river banks. Giant hogweed can cause harm to human health.
Some native plants may require control:
This guide describes your legal obligations regarding non-native plants and invasive plants; how to identify and control invasive plants, using methods such as spraying, digging up, cutting and burning; and how to remove and dispose of them.
Relevant Business Topics:
Scottish Natural Heritage - non native species
Invasive non-native plants are species which have been brought into the UK that have the ability to spread causing damage to the environment, the economy, our health and the way we live.
Invasive plants are listed in schedule 9 of the Wildlife (Northern Ireland) Order 1985, as amended by section 27 schedule 1 of the Wildlife and Natural Environment Act (Northern Ireland) 2011.
If you have invasive plants on your premises you have a responsibility to prevent them spreading into the wild or causing a nuisance.
You must not plant or otherwise cause to grow in the wild any plant listed on schedule 9 of the Wildlife and Countryside Act 1981.
If you have invasive plants on land that you own or occupy, you must comply with specific legal responsibilities, including:
You do not need to notify anyone about the invasive plants on your land. However you should record and report non-native species. See the page in this guideline: Reporting of non-native species.
Noxious weeds are native species whose productivity is considered able to cause harm to agriculture. In Northern Ireland the seven species of noxious weed are:
If you have any noxious weeds on your land, you are responsible for controlling them. You must prevent them from spreading onto adjoining land.
Non-native plants are those species that have been brought into Scotland. Some of these become invasive - with the ability to spread, causing damage to the environment, the economy, our health and the way we live.
Moving soil contaminated with non-native species from one place to another, or incorrectly handling and transporting contaminated material and plant cuttings, can cause these plants to spread into the wild. In Scotland it is forbidden to plant or cause to grown in the wild, any non-native plant.
If you have non-native plants on your premises you have a responsibility to prevent them spreading into the wild. For those plants that are known to be invasive, you should take steps to avoid them causing damage or becoming a nuisance.
If you are controlling non-native plants on land that you own or occupy, you must comply with specific legal responsibilities, including:
You do not have to report any plant species in Scotland. However you can support the efforts being made to map the extent of invasions by reporting non-native species.
Injurious weeds are those that are considered able to cause harm to agricultural pasture. The five species of 'injurious weed' are:
If you have any injurious species on your land, you can be required to control them, if:
It is important that you can identify invasive plants on your premises. This will allow you to manage and deal with them in the most appropriate way.
Identifying invasive plants on a site early lets developers assess and cost options for destroying, disposing of and managing them.
Managing land infested by invasive plants in a timely and appropriate way can avoid:
Japanese knotweed begins to grow in early spring and can grow in any type of soil, no matter how poor. It can grow as much as 20 centimetres per day, and can reach a height of 1.5 metres by May and 3 metres by June. It does not produce viable seeds in the UK, but instead spreads through rhizome (underground root-like stem) fragments and cut stems. Japanese knotweed:
You should take great care when identifying giant hogweed. Contact with the plant, particularly the sap, can lead to severe blistering and scarring.
Giant hogweed closely resembles native cow parsley or hogweed. It can take four years to reach its full height of 3-5 metres and flower. Giant hogweed:
Himalayan balsam is often found on river banks, growing up to 2 metres in height. Each plant lasts for one year and dies at the end of the growing season. Himalayan balsam:
Other species of invasive plants in the UK include:
You do not need to notify anyone about any plant species. However you can support the efforts being made to map the extent of invasions by reporting non-native species.
To report a sighting of a non-native species it is useful to:
To remove invasive plants from your premises or to stop them from spreading, it helps to understand how new plants grow and spread. This will help you decide what action to take.
If you employ a contractor to do the work for you, you should understand what they intend to do and why. This could help you decide what you actually need and could save you money.
Japanese knotweed does not spread from seeds in the UK. It is spread when small pieces of the plant or rhizomes (underground root-like stems) are broken off. One piece of rhizome or plant the size of a fingernail can produce a new plant.
Pieces of plant or rhizome can be transported to a new location by:
Individual plants can cover several square metres of land, joined up below ground by an extensive rhizome network. Herbicide treatment can be a very effective way of controlling Japanese knotweed, but a lack of regrowth does not mean the underground rhizome is dead. If the soil is disturbed, knotweed often regrows.
Giant hogweed produces large, umbrella-like flowers, each of which can produce up to 50,000 seeds. These seeds fall typically within 4 metres of the parent plant. Seeds can be transported by:
The seeds can remain dormant in the soil for 15 years. Even if you treat the plants with herbicides and they die, several thousand seeds are waiting in the ground below for the opportunity to take their place. Any control programme needs to continue for several years, including checks for new growth. When managing giant hogweed it is important to maintain a healthy grass sward, either by using selective herbicides or by sowing grass mixes. A dense grass sward helps to prevent giant hogweed seeds from germinating.
Giant hogweed contains sap that is released when the plant is cut or by brushing against the plant. Contact with the sap causes skin to become sensitive to sunlight, resulting in painful blisters which appear up to two days after contact and may reoccur for several years.
Himalayan balsam plants can produce around 2,500 seeds each year. The seedpods open in such a way that the seeds are thrown up to 7 metres away from the parent plant, helping the species to quickly spread. Seeds can also be transported by:
Even if you remove these plants, or treat them with herbicides and they die, several hundred seeds can be waiting in the ground below for the opportunity to take their place. The seeds can survive for several years, so any control programme needs to continue for a couple of years, including checks for new growth.
If you do not manage invasive plants correctly, they will spread over time and they could cause damage to structures, such as building foundations.
If you have invasive plants on your site you should put up signs, where appropriate, to warn employees and the public about the invasive species that are present.
Put up posters in offices and communal areas to explain to employees what the problems are and what they need to do. Include pictures of the invasive plants you have on your site. This is particularly important for giant hogweed, as contact with sap from the plant can lead to skin burns.
SEPA has produced a guidance note that deals with biosecurity and invasive non-native species (INNS). It is of use to developers and anyone working close to water:
Make sure your staff can identify Japanese knotweed rhizomes (underground root-like stems). This can reduce waste costs and improve how you manage Japanese knotweed on site.
You should minimise the amount of soil containing Japanese knotweed material that you excavate. Soil containing Japanese knotweed material that has been treated can be reused for landscaping the site, but should not be taken off site, unless to landfill.
You have a choice of herbicides that are effective against Japanese knotweed, depending on your situation.
See the page in this guideline: Spraying invasive plants with herbicide.
On development sites you should fence Japanese knotweed where possible, using clear signs so that only appropriately briefed personnel enter the enclosure to deal with the infestation and resulting waste. This includes areas with waste plant material or soil contaminated with Japanese knotweed. The fence should be at least 7 metres away from the plants. Put up restricted access signs around these fenced areas (poster available in Appendix VII of the Japanese knotweed code of practice). You must not use tracked vehicles within the affected area, and make sure any vehicles leaving the area are pressure washed.
You must never strim areas containing Japanese knotweed. If you are going to clear areas where Japanese knotweed is present, make sure you remove all cut stems.
See the page in this guideline: Disposing of invasive plants and contaminated soil off site
Do not try to compost Japanese knotweed material - it will produce new plants. You must not put cut plant material directly onto the ground. If you must stockpile cut material, make sure it does not come into contact with soil - for example, by placing it on top of a barrier membrane.
See the page in this guideline: Cutting and burning invasive plants.
Keep soil containing Japanese knotweed material separate from clean soil. This will reduce the volume of soil that you need to treat and dispose of.
When giant hogweed sap comes into contact with skin, it reacts with sunlight and causes chemical skin burns. Giant hogweed sap becomes more toxic as the year progresses and the plant is exposed to more sunlight.
The stem and underside of the leaves have hairs like a stinging nettle. Brushing against giant hogweed can be enough to get sap on your skin.
If you have giant hogweed on your premises, you must ensure that the public and your employees are protected from the hazards of its toxic sap.
You should control giant hogweed before it seeds. You must not use a strimmer on giant hogweed. The sap from the plant may get onto your skin or into your eyes.
If you are going to get close to or handle giant hogweed, you should wear full protective clothing with gloves, a hood and a full-face visor. You should wash down your protective clothing before you take it off.
If you get sap on your skin, cover it to keep it out of the sun. Go indoors immediately and wash the sap off your skin with soap and lots of water.
Treating invasive plants with herbicide can be a very effective method of treatment. You will have to respray. It usually takes at least three years to treat Japanese knotweed. Giant hogweed seeds can continue germinating for 15 years after the last seed fall.
If the plant is in or near to water, in Northern Ireland you must have agreement from the Northern Ireland Environment Agency (NIEA) to use the herbicide. The herbicide must be approved for use in or near water.
In Scotland, If the invasive plant is in or near to water, i.e. within 1 metre of the top of the bank, you can apply herbicides under a general binding rule (GBR 23g). So long as you comply with the requirements of the GBR you do not need to contact SEPA. A CAR licence will be required for plants growing next to watercourses that are not invasive non-native plants, and for applying herbicides directly to the water (eg treating submerged plants.
The herbicide's effectiveness depends on the type used. An advisor certified by BASIS (the registration, standards and certification scheme for pesticides and fertilisers) will be able to advise you on the most suitable type of herbicide for your situation and when best to apply it.
Giant hogweed and Himalayan balsam both drop large quantities of seeds. A control programme will need to continue for several years, with checks carried out throughout the growing season. If you are trying to eradicate these plants from a riverbank it is important to ensure that any plants upstream are also treated to avoid seeds being washed onto the site.
Japanese knotweed has a large underground network of rhizomes (underground root-like stems). To eradicate the plant you must kill the rhizomes. Picking the right herbicide is essential, as it must travel through the plant and into the rhizome system below. Several herbicides can treat Japanese knotweed successfully - you will need to pick the right herbicide for your situation. Glyphosate is effective because it penetrates through the whole plant.
The person doing the spraying must hold a certificate of technical competence for herbicide use or work under the direct supervision of a certificate holder. If you plan to spray in or near water, the person carrying out or supervising the spraying must have the appropriate aquatic part of the qualification. The sprayer must also comply with the pesticide product label and meet all of its conditions. Before you spray in or near water you must check that the product is approved for use near water.
You can get a certificate of technical competence by attending a short course at an agricultural college or similar institution.
For herbicide to be effective, make sure you use it at the correct time of year:
You must follow the guidance in the statutory code of practice for plant protection products. If you follow its advice you should stay within the law.
You must make sure that your pesticide application equipment is tested when five years old. Rucksacks and handheld sprayers are exempt. From 26 November 2015 Grandfather Rights expire (they may have applied if you spray on your own or your employers land) and pesticide spraying must always be carried out by someone with the appropriate certificate.
If the invasive plants are near a watercourse, consideration should be given to mechanical removal methods, where possible. See the Cutting and burning invasive plants page. If you are planning to use herbicide in or near to a watercourse, you must consult the NIEA or SEPA. In Scotland you can apply herbicide to an invasive non-native plant, growing within 1 metre of the top of the bank, under the conditions set out in GBR 23g.
You must also carry out a Control of Substances Hazardous to Health (COSHH) assessment for any activities that involve herbicides.
You must make sure that all your waste is stored, transported and disposed of safely. Waste herbicides are likely to be classed as hazardous/special waste. You must keep this separate from other waste.
Herbicide containers must either be rinsed or handled as herbicides. Check product labels to see if your waste containers should be rinsed. Water used for rinsing empty containers is classed as dilute pesticides or biocides.
In Northern Ireland, you may need a groundwater authorisation, registered waste exemption or trade effluent consent to dispose of water used for rinsing empty containers.
In Scotland you may need an authorisation or permission to dispose of water used for rinsing empty containers. Contact SEPA for further information.
Clearing the leaves and stems of Japanese knotweed or giant hogweed that are above ground and then removing soil contaminated with roots, rhizomes (underground root-like stems) and seeds can provide faster results than just spraying with herbicide.
Try to minimise the amount of waste you generate that contains invasive plants, or their seeds and rhizomes. Any waste you do produce should be treated on site where possible.
Any waste that is taken off site must be taken by a licensed waste carrier and must go to a suitably authorised landfill site.
If you intend to bury invasive plant waste on your property you must contact your environmental regulator to check you are allowed to do this at your location.
See the page in this guideline: Burying invasive plant material on site.
You should not remove soil from river banks, as this can cause water pollution. If you are planning to carry out work near a river you should contact the Northern Ireland Environment Agency (NIEA) or Scottish Environment Protection Agency (SEPA).
If your site floods, the seeds will be spread further across the site, so you will need to manage a larger area.
To clear ground contaminated with giant hogweed, you may need to remove soil up to 4 metres away from the plants and to a depth of 0.5 metres. You will need to check for regrowth regularly. You should spray regrowth with the herbicide glyphosate before the plants flower.
The rhizome system beneath a stand of Japanese knotweed can be over 4 metres deep and could extend for at least 7 metres around the stand. If you are going to dig out the rhizome system you will need to remove all of the plant material. You should use the rhizome identification guide in the knotweed code of practice, or ask a specialist, to help you identify the plant material.
You will need to check any cleared areas regularly for regrowth. You can spray any regrowth with herbicide.
To clear ground contaminated with Himalayan balsam, you may need to remove soil up to 6 metres from the parent plant and to a depth of 0.5 metres. You should not remove soil while the seed pods are present. You will need to check for regrowth regularly. You should pull by hand or strim regrowth before the plants flower.
However, as seeds remain viable in the soil for several years, annual cutting, mowing or grazing or annual herbicide treatment during the spring growing season can be an effective control for this plant. You must also carry out follow up checks for late germinating seeds.
Never stockpile contaminated soil or plant material within 10 metres of a watercourse or within 7 metres of your site boundary.
Collect any water you use for cleaning vehicles that are used in contaminated areas. If it is contaminated with seeds or plant material, you must not discharge it to a watercourse. You could treat the water by passing it through a settlement tank to remove any soil before passing it through a very fine mesh sieve to remove seeds or plant material. Settlement alone may not be adequate because seeds and plant material float.
You may be able to deposit material sieved from water used for vehicle washing in a controlled area on your land and monitor it for regrowth. You should speak to the NIEA or SEPA to determine your best option.
DAERA: Invasive alien species Advice for planning officers and applicants seeking planning permission on land containing invasive alien species
Cutting down or digging up invasive plants and burning the waste plant material can be a useful, low-tech means of control. It can reduce the volume of waste that you need to dispose of off site.
Cutting Japanese knotweed will, over time, weaken the plant, but it will not kill the rhizomes (underground root-like stems). It can be used as part of other control practices. You must not use a strimmer on Japanese knotweed.
You must handle and dispose of cut plant material carefully.
Cutting giant hogweed before the plants flower will help to prevent further seeds being deposited on the ground. This is an effective way of removing these species but it can take many years. You must not use a strimmer on giant hogweed.
You must avoid contact with giant hogweed, particularly its sap, as it can cause chemical skin burns. You should wear full protective clothing when working near it or handling it. Giant hogweed sap remains toxic after the plant has been cut down. Do not leave cut stems where they could harm people or livestock.
Pulling up Himalayan balsam within four weeks of the first flowers being seen is the most effective method of control. Do not cut the plants before they flower as this can result in a more bushy plant that produces more flowers. The best time to cut is late May. Cut the plant below the first nodule. Make sure you place cut Himalayan balsam material on a membrane and not in direct contact with the ground.
Burning plant material should only give rise to white smoke.
Tell the local fire brigade before you begin burning and again when you finish, so that they are not called out unnecessarily
If you burn waste in the open, you may require a waste management licence or exemption.
Waste Management Licences
You may qualify for a paragraph 30 exemption to burn certain waste plant tissue and untreated wood if you:
If you have an exemption, you must comply with the exemption objectives and register this exemption:
You must also ensure that your activity does not:
In Northern Ireland you must notify the NIEA at least a week before you intend burning plant material. You should also notify your district council environmental health officer before you begin burning plant material.
In Scotland you should notify your local authority environmental health officer before you begin burning plant material.
If you burn waste in an incinerator or other similar plant, you may need a pollution prevention and control permit.
Taking plant material and soil containing plant material away for disposal off site uses valuable landfill capacity and increases the likelihood of the spread of invasive plants. Another option is to bury this soil and plant material on your own land because, without sunlight, plants cannot survive and seeds will not germinate.
However, this material will need to remain buried for several years to ensure that it will not grow again. Giant hogweed seeds can be viable for up to 15 years and Japanese knotweed rhizome (underground root-like stems) is believed to survive for 20 years.
Soil and plant material containing Japanese knotweed may need to be buried 5 metres below ground level. You should place a barrier membrane on top of the material and fill the hole with clean soil. In some situations, alternative methods which do not require such deep burial are available.
Soil containing Himalayan balsam and giant hogweed seeds should be buried at least 1 metre below ground level.
You must not bury anything other than plant material and soil containing invasive plants that have originated on site.
You must make sure that deep burial does not interfere with the ground water level.
Buried soil and plant material that have been treated with a herbicide that does not break down in the environment could cause groundwater pollution. If you intend to bury treated material, you should treat it with glyphosate herbicide only. Check with the NIEA or SEPA.
Herbicides that do not break down in the environment are described as persistent. Those that do break down are described as biodegradable or non-persistent. The herbicide packaging or safety data sheet will state whether it is persistent or non-persistent.
Soil contaminated with some persistent herbicides will be classed as hazardous and so will need to be disposed of as special waste.
You must follow the guidelines for spraying plants with herbicide and digging up plants.
You should bury the material in an area where it is not likely to be disturbed. You should keep records of the quantity of material that you have buried and a map showing the location of the burial pit and its depth. Use signs to mark the burial pit and keep heavy tracked machinery off the area.
You should not bury materials deeply within 7 metres of an adjacent landowner's site.
You should try to minimise the amount of waste you generate that contains invasive plants or their seeds, roots and rhizomes (underground root-like stems). Any waste you do produce should be treated on site where possible.
Any waste taken off site must be taken by a licensed waste carrier and go to a suitably authorised landfill site.
When you transport invasive plants and soil contaminated with invasive plants, make sure that the vehicle is covered or sheeted so that seeds and plant material cannot blow away. If you allow contaminated soil or plant material to escape, you could be prosecuted and fined.
You must have waste transfer notes (WTNs) for any material leaving your site. You must list any material that contains invasive plants or their seeds on the WTN. Your waste carrier can only take the waste containing invasive weeds to sites authorised to accept it. Plant material, or soil containing plant material or seeds, is likely to be classed as non-hazardous waste - this is a different category from inert waste.
There is a duty of care for waste that affects all businesses. You must make sure that:
You must take waste plant material or contaminated soil to a site that has a pollution prevention and control permit or waste management licence.
The conditions of the permit or licence must allow the disposal of invasive plants at the site. You should check with the waste site in advance to make sure they can accept material containing invasive plants.
The waste site may need notice so that an area can be prepared. For example, a landfill site will need an area away from the landfill liner for material containing invasive plants.
Land remediation relief (LRR) is a corporation tax relief scheme introduced to help bring land that has been ruined by various industrial uses or long-term neglect back into productive use. You may be able to claim LRR for removing contamination arising from Japanese knotweed. You will not be able to claim LRR if disposing of material containing Japanese knotweed to landfill.
This page provides links to the full text of key pieces of environmental legislation relating to invasive weeds. The websites hosting the legislation may list amendments separately.
If you are setting up an environmental management system (EMS) for your business, you can use this list to start compiling your legal register. Your legal adviser or environmental consultant will be able to tell you if other environmental legislation applies to your specific business.
Environmental Management Systems (EMS) and environmental reports
Noxious Weeds (Northern Ireland) Order SI 1977/52. Defines ragwort, thistle, dock and wild oat as noxious weeds and places a legal responsibility on landowners to prevent the spread of these weeds.
Wildlife and Countryside Act 1981. Bans certain methods of killing or taking wild animals, including birds, and restricts the introduction and sale of certain non-native animals and plants. Also sets out the amended laws relating to public rights of way.
Wildlife (Northern Ireland) Order SI 1985/171. (As amended) It is an offence under Article 15 if anyone plants or otherwise causes to grow in the wild any species of plant listed on Schedule 9 Part II.
Wildlife and Natural Environment Act (Northern Ireland) 2011. Includes new provisions and amends the Wildlife (Northern Ireland) Order 1985 and the Environment (Northern) Order 2002 to give protection to a greater range of plants, animals and birds, and to increase protection to Areas of Special Scientific Interest. Gives enforcement authorities new powers and sanctions against perpetrators of wildlife crime.
Weeds Act 1959. Provides a power for Ministers to serve orders requiring the control of injurious weeds.
Wildlife and Countryside Act 1981. Bans certain methods of killing or taking wild animals, including birds, and prohibits the release or planting of non-native species. Also contains powers to create secondary legislation further governing the use of the non-native species. See more details.
Environmental Protection Act 1990. Defines the legal framework for duty of care for waste, contaminated land and statutory nuisance.
Wildlife and Natural Environment (Scotland) Act 2011 Extends the regime for controlling non-native species and introduces new wildlife offences.
You may also need to know about and comply with legislation on:
The Northern Ireland Environment Agency has published a short guide to the duty of care responsibilities including advice and information for waste producers, carriers and those accepting, storing and treating waste.
Any person intending to alter the use or management of areas of uncultivated or semi-natural land must obtain prior approval from the Department of Agriculture, Environment and Rural Affairs (DAERA).
Read more on the DAERA website
The NetRegs team at SEPA, in partnership with The Northern Ireland Environment Agency, Natural Resources Wales and a number of industry bodies have produced 9 new GPPs to replace out of date PPGs. More are coming! Check the available topics
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