Invasive species law in 2026: what UK landowners need to know
A plain-English guide to the regulatory landscape facing UK property owners and developers in 2026 — Schedule 9, the IAS Order, EA/NRW notification thresholds and biosecurity duties.
There has not been a major new statute on invasive species in 2026, but a steady stream of case-law, regulator guidance and landfill-tax tightening has changed the practical position for property owners. Here is the working summary every solicitor, landowner and developer should understand this year.
Schedule 9 of the Wildlife and Countryside Act 1981
Section 14(2) makes it an offence to plant, or to cause to grow in the wild, any plant listed in Schedule 9. The list includes Japanese knotweed, giant hogweed, Himalayan balsam, rhododendron ponticum, New Zealand pygmyweed, three-cornered garlic, parrots feather and floating pennywort. "Cause to spread" is interpreted broadly — soil movement, contaminated machinery, fly-tipping of garden waste all count.
The Invasive Alien Species Order 2019
This is the UK-retained version of EU Regulation 1143/2014. It prohibits the keeping, breeding, transport, sale, exchange or release of listed species. In 2026 the list is unchanged from 2024 and covers 36 plants of UK concern. APHA enforces it for trade and movement; Defra publishes the list.
Duty of Care under the EPA 1990
Soil containing Japanese knotweed rhizome is classified as controlled waste. Any movement off-site — even to next-door — must be covered by a registered waste-carrier note and tracked to a licensed disposal facility. The fine on summary conviction has risen with inflation and is now £5,000+ in 2026.
Civil nuisance and encroachment
Following Williams v Network Rail (2018) and the line of authority since, encroachment of knotweed (and increasingly bamboo) onto a neighbour's property gives rise to a private nuisance claim. Damages are awarded for diminution in value and the cost of treatment. We are now seeing equivalent cases reach the County Court for running bamboo at a rate of roughly one a month in 2026.
Regulator notifications
- Environment Agency (England) — RPS 178 covers on-site treatment of knotweed without further notification, provided conditions are met.
- Natural Resources Wales — equivalent position statement applies in Wales.
- Bund burial on development sites requires prior site-specific written notification.
- Treatment within 8 m of a watercourse requires aquatic-approved herbicide and a separate notification.
Frequently asked questions
- Is it illegal to have knotweed on my property in 2026?
- No. It is only an offence to cause it to spread into the wild or onto neighbouring land. Doing nothing on your own land is not, of itself, a criminal offence — but it may create civil liability if the plant encroaches.
- Do I need to notify the Environment Agency before treatment?
- Not for standard on-site herbicide programmes — RPS 178 covers this. Bund burial and excavation with on-site disposal do need site-specific notification.
Reviewed by
The survey team
PCA-certificated surveyors, Japanese Knotweed Elimination
PA1 / PA6A certificated surveyors who carry out the site visits, write the management plans and sign off the reports issued to lenders and solicitors.
Reviews the technical, legal and lender statements in this article.
What this page can't tell you
- Guidance is general. Identification, treatment choice and timescales can only be confirmed by a site visit — photographs alone are indicative.
- Lender and insurer requirements vary by institution and change over time. We state what is typically accepted, not what any named lender will accept on your case.
- Guarantee (IBG) eligibility depends on the plan chosen, the survey findings and the underwriter's acceptance. It is not automatic.
- Legal points summarise published law and guidance current at the review date. They are not legal advice.
Last reviewed · Questions on anything stated here: 07582 869979
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