Juncus gerardii (Saltmeadow Rush, Black Grass) is a grass-like plant, with sprays of dark brown florets. This plant native to the East Coast from Newfoundland to Virginia, and broadly in Eurasia, in where it occurs near the upper tide limits of marshes and beaches. It is 100 to 800 mm tall. It spread inland to sites in the Midwest in the Great Lakes region, in the 1800s including saline wetlands, railroad beds and other disturbed areas. It was first found on the Pacific Coast in Victoria, British Columbia in 1887, and found on San Juan Island, Washington in 1917. It has been found in brackish marshes in on the Oregon Coast, and in Contra Costa and Solano counties, on San Francisco Bay, and Willapa Bay. In 2006, it was found only in Southampton Marsh, Benicia, Solano County (Baye 2007), but has been spreading, It occurs in at least 10 sites on the central Oregon Coast. Possible vectors include dry ballast, and, around San Francisco Bay, more recent plantings of Spartina alterniflora for habitat restoration.