Naturenet: Weeds

Noxious or otherwise


eeds! Every gardener’s nightmare. Also a problem for the countryside manager. Although it is rarely the first option, weed control is still a necessary activity in many places - either because of invasive introduced species, or because of natural species which don't co-exist happily with the way we want to use our land. There are a number of plants which are regularly controlled and which have various bits of law attached to them. This page tries to simplify the maze with some straightforward advice and links to more information.


RagwortWhat a lot of fuss is made over the humble ragwort! It's a natural part of the British ecosystem, but it does have a habit of invading overgrazed pasture, and if horses (in particular) eat it, it has a long-term poisonous effect and can even kill them. It also affects other grazing livestock. Because people like and value horses there are often campaigns and exhortations to 'root out ragwort', and even some optimistic souls asserting that it can be eradicated - which is neither possible nor desirable. Without doubt, though, some degree of control is a good idea. What is less helpful is some anti-ragwort campaigners repeating dubious statements such as suggesting that ragwort can kill a horse without even growing in its field, or that there has been some sort of recent 'plague' of ragwort, or that ragwort population is anything to do with cinnabar moths - none of these are true, and these and similar alarmist claims only serve to confuse the conscientious landowner who wants to know what to do about the weed.

Ragwort and the law
It's often said that it's illegal to have ragwort growing on your land. it isn't. Under the Weeds Act 1959 the Secretary of State may serve an enforcement notice on the occupier of any land on which injurious weeds are growing, requiring the occupier to take action to prevent the spread of injurious weeds. If the landowner dosn't clear up the weeds, the government can do it for them, and charge them. So it's not actually illegal.

The Weeds Act specifies five injurious weeds: common ragwort, spear thistle, creeping or field thistle, broad-leaved dock and curled dock. Ragwort is by far the most common and significant of these. The government department that has the enviable job of serving these notices is DEFRA. However, they do not act on every case, and indeed they are not obliged to do so. Their policy is that a priority will only be given to complaints where weeds are threatening land used for:

So, not only is it not illegal to have ragwort on your land, but unless it is directly threatening to spread onto agricultural land, nobody will do anything about it. Where there is a risk that injurious weeds may spread to land which is not farmland there is no legal remedy under the Weeds Act. The best way forward is for the complainant to discuss the problem with the occupier of the infested land. They may be able to work together to achieve a satisfactory outcome. Ultimately, however, if this is not possible, an occupier of land under threat from weeds may need to consider civil action through the courts - pretty unlikely to achieve much.

What to do about ragwort
There's much more information available from DEFRA (see link below) but in short, you can pull it up, cut it or poison it.

Whatever method you use, you will need to do it again and again. Also, if you don't get the management of the land right (usually introducing less intensive grazing and reducing supplementary feeding) you will never control it either. Good pasture management which keeps the grass sward tight will minimise the chance of ragwort establishing.

Ragwort: links
DEFRA: weeds page
Ragwort Control Act 2003
Ragwort Facts: dispels some bizarre myths about ragwort, and gives good references.

Japanese Knotweed

KnotweedKnotweed is an invasive introduced plant that colonises waterways and woodlands, and pushes out native wildlife. It gets to be very tall, forms dense stands, and is an impressive sight. Originally a garden plant, it now gets everywhere and is a nuisance particularly as its strong roots can break through concrete and damage buildings. It's particularly problematic in the West Country and Wales.

Knotweed and the law
Like ragwort, it's not actually illegal to have knotweed on your land. But it's not a good idea. In the UK there are two main pieces of legislation that cover Japanese Knotweed. These are:

If you have a neighbour who has knotweed and it is spreading onto your land, it would be a very good idea to take action before it gets near your buildings. Start with friendly discussions, but if that goes nowhere, it might be time to consult your buildings insurance company (some will act for you in such matters) or a solicitor.

What to do about knotweed
There's only really one thing to do: poison it. No other method really works, and anything involving digging or cutting has such a high risk of spreading the plant it's probably not worth it. A bit of plant the size of a postage stamp can sprout into a whole clump within a single growing season. Application of glyphosate (Round-up) can control it if you are lucky, but for anything more than a few stems you really need to get qualified help in to do it properly. Unfortunately it is a hard plant to poison, and often resists applications effectively. Commercial herbicides are stronger than those bought over the counter and a trained operative will know the best way to get at this particularly difficult plant.

Knotweed links
Environment Agency: knotweed page
Cornwall Knotweed Forum: good general information too
Devon CC knotweed page


BrackenAnother native species, in days gone by bracken was harvested extensively for fire-lighters and animal bedding. But with the change in agricultural patterns and harvesting, now in some places, especially heathland and moorland, bracken can be an invasive species which out-competes many other scarcer plants. Thus it is often the target of control activity.

Bracken and the law
There is no legal obligation to control bracken and there is no particular legislation about it.

What to do about bracken
Generally, bracken problems tend to be on large areas, and so the solutions are often large scale -including ariel spraying, burning, ploughing and many other methods. If you want to do this, you need more technical advice than we can offer. However, for small-scale bracken control pulling and crushing are moderately effective. Both need to be carried out for many seasons to exhaust the rhizomes, and in some places spraying with herbicide can be effective, but as bracken is usually in a place where other species grow you should definitely get a professional to do this if you chose the chemical option.

Bracken and health: bracken contains cancer-causing chemicals, and the stems can very easily cut the hands. So wear gloves when pulling or handling it, and don't eat it. There was a time when people working in bracken areas wore masks to avoid breathing in the spores, but this is now uncommon as the risk of harm is known to be very low.

Bracken links
SEPA leaflet: very comprehensive - PDF file (500kb).
RSPB advice