In Northern Ireland The Wildlife Order (NI) 1985 (as amended) states that 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.
This also applies if anybody releases or allows to escape into the wild, any animal included in Part 1 of Schedule 9.
However, it is not actually an offence to have invasive plants such as Japanese Knotweed present on your land – landowners also have rights with respect to their private property and what they can ‘grow’ in their gardens.
You can also have some animals species as long as they are properly confined and cannot escape into the wild.
There is perhaps a community expectation within society that owners of property and land look after such assets responsibly but it is important to highlight that, in both National and EU legislation, the Northern Ireland Environment Agency’s policy context towards all Invasive Alien Species is one to assist protect the ecology of an area as opposed to safeguarding property or other commercial assets. Therefore, where species such as Japanese knotweed are spreading from one private property to another, it constitutes a civil matter between the two landowners.
If a landowner were to remove either Japanese knotweed or Giant Hogweed (both of these species are classified as ‘controlled waste’ ) from a site in an inappropriate way, in other words not using properly licensed hauliers, Waste Transfer Notes and delivering the material to licensed landfill facilities.
But that would not be an offence under wildlife legislation, it would be a breach of NI Waste Legislation.
If a landowner is disposing of knotweed, or any other controlled waste, by cuttings or by excavation The Waste and Contaminated Land (Northern Ireland) Order 1997 (as amended) articles 4 (1a) and 4 (1b) is relevant. This legislation places a duty of care on “anyone who produces, collects, carries, keeps, treats or disposes of controlled waste to take all the necessary steps to keep it safe and to prevent it from causing harm, especially to the environment or to human health”
The Northern Ireland Environment Agency provide an online service to allow you to search for appropriately licensed waste sites. This is available on the DAERA website at: http://www.daera-ni.gov.uk/articles/waste/registered-waste-carriers-transporters