Himalayan knotweed Persicaria wallichii
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A non-native invasive plant.
This plant is similar to Japanese knotweed, but has longer, pointed leaves. It’s a large, thicket-forming plant, reaching up to 2m tall, and has become established on stream sides, hedge banks, woodland edges, roadsides, railway banks and waste ground.
This plant was introduced as a garden plant in Victorian times, but is much less popular today. It is still present in some gardens and is still available commercially from some nurseries.
As with similar plants (like Japanese knotweed), Himalayan knotweed grows on stream sides, hedge banks, woodland edges, roadsides, railway banks and waste ground.
What's the problem?
Once established this plant grows into extremely dense stands that out-compete all native vegetation.
Rapid Risk Assessment
***** Critical Risk
This is a species that Plantlife believes should be listed on Schedule 9 of the Wildlife and Countryside Act in England and Wales.