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Species · Flowering plants

Marshpepper Knotweed

Persicaria hydropiper

2,959Records since 2000
AugustPeak month
75Counties with records

When it is recorded

Jan0
Feb2
Mar3
Apr1
May66
Jun338
Jul602
Aug868
Sep517
Oct69
Nov4
Dec0

GBIF records by month, 2000–2025 (all years combined).

Where it is recorded

#CountyNationRecordsShare
1Worcestershire England466
2Powys Wales196
3Gwynedd Wales140
4Pembrokeshire Wales123
5Carmarthenshire Wales122
6Argyll and Bute Scotland114
7Ceredigion Wales84
8Norfolk England74
9Devon England68
10Monmouthshire Wales58
11Fermanagh and Omagh Northern Ireland56
12Denbighshire Wales53
13Surrey England49
14Essex England41
15Wrexham Wales34
1,540 England153 Scotland1,067 Wales92 Northern Ireland

Records per county (GADM level 2) and per nation; one record can count towards several areas. 75 counties in all.

About this species

Records since 2000
2,959
Peak month
August
Counties with records
75
Scientific name
Persicaria hydropiper
Also known as
Water-pepper
Group
Flowering plants
NBN Atlas records since 2000
20,605
Conservation designations
GB Red List (2001 IUCN criteria)
Kingdom
Plantae
Phylum
Tracheophyta
Class
Magnoliopsida
Order
Caryophyllales
Family
Polygonaceae
Genus
Persicaria
Name with authority
Persicaria hydropiper (L.) Spach
Contributing datasets
41

Sources: GBIF occurrence data (CC0 / CC BY), JNCC Taxon Designations (OGL), NBN Atlas (open licences), Wikidata (CC0) · GBIF 8323622