black-grass
- kingdom: Plantae
- phylum: Tracheophyta
- class: Magnoliopsida
- order: Magnoliales
- family: Juncaceae
- genus: Juncus
- species: Juncus gerardii
- Jois
Burgenland
Austria- Nanaimo
British Columbia- Saint Andrews
- Saint John
New Brunswick- Charlottetown
Prince Edward Island- La Malbaie
- Rivière-du-Loup
Quebec
Canada- Corbie
B6
France- Keramotí
East Macedonia and Thrace
Greece- Koewacht
- Sas van Gent
- Sluis
Zeeland
Netherlands- Hasslö
- Jämjö
- Karlshamn
- Karlskrona
- Sturkö
- Sölvesborg
Blekinge- Klintehamn
- Slite
Gotland- Nässjö
Jönköping- Luleå
Norrbotten- Holmsund
- Hörnefors
- Nordmaling
- Röbäck
- Umeå
Västerbotten- Bergeforsen
- Härnösand
- Johannedal
- Stockvik
- Sundsbruk
- Timrå
Västernorrland- Jursla
- Krokek
- Lindö
- Söderköping
- Valdemarsvik
- Åby
Östergötland
Sweden- Jarrow
- Newbiggin-by-the-Sea
England
United Kingdom- Crockett
- Martinez
- Mountain View
California- Denver
Colorado- Bridgeport
- Fairfield
- Orange
- Southport
- Stamford
- West Haven
- Westport
Connecticut- Lewes
Delaware- Kokomo
Indiana- Kittery
- Wells Beach Station
Maine- Deale
- Dundalk
- Severna Park
- Solomons
Maryland- Cambridge
- Danvers
- Dighton
- Essex
- Gloucester
- Harwich
- Harwich Port
- Ipswich
- Nahant
- Nantucket
- Orleans
- Quincy
- Somerville
Massachusetts- Moorhead
Minnesota- New Castle
New Hampshire- Barnum Island
- Borough of Bronx
- Borough of Queens
- Brooklyn
- Cayuga Heights
- Cold Spring Harbor
- East New York
- Galeville
- Halesite
- Harbor Isle
- Hartsdale
- Huntington
- Huntington Bay
- Inwood
- Island Park
- Kings Park
- Lansing
- Laurel Hollow
- Long Beach
- Massapequa
- Massapequa Park
- North Massapequa
- Northville
- Pelham Manor
- Rye
- Sag Harbor
- Scarsdale
- Seaford
- Staten Island
- Syracuse
New York- Fargo
North Dakota- Providence
Rhode Island- Alexandria
- Belle Haven
Virginia- Geneva
- Seattle
- Silverdale
Washington
United States