coast amaranth vs Coast Barnyard Grass

Amaranthus pumilus compared with Echinochloa walteri

Key Differences

• coast amaranth is Extinct while Coast Barnyard Grass is Least Concern.

Taxonomic Classification

Rank	coast amaranth	Coast Barnyard Grass
Kingdom same	Plantae (Plants)	Plantae (Plants)
Phylum same	Magnoliophyta (Flowering Plants)	Magnoliophyta (Flowering Plants)
Class	Magnoliopsida (Dicots)	Liliopsida (Monocots)
Order	Caryophyllales (Caryophyllales)	Poales (Grasses)
Family	Amaranthaceae	Poaceae (Grass Family)
Genus	Amaranthus	Echinochloa
Species	Amaranthus pumilus	Echinochloa walteri

Evolutionary Relationship

coast amaranth and Coast Barnyard Grass share a common ancestor at the Phylum level: Magnoliophyta. (Flowering Plants)

Conservation Status

coast amaranth

EX — Extinct

Coast Barnyard Grass

LC — Least Concern

Physical Characteristics

Attribute	coast amaranth	Coast Barnyard Grass
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

coast amaranth

Habitat

Typically found in diverse terrestrial habitats from tropical forests to temperate regions.

Range

Found in Japan.

Coast Barnyard Grass

Habitat

Typically found in grasslands, wetlands, forests, and cultivated landscapes.

Range

Distributed across Brazil and Canada.

coast amaranth

Coast amaranth (Amaranthus pumilus) is an annual herb in the family Amaranthaceae, native to the Atlantic and Gulf coasts of the eastern United States, where it once grew on coastal foredunes, beach strand, and shell-hash substrates above the high tide line from New York south to South Carolina. It is a low-growing, fleshy plant with small, rounded leaves and inconspicuous green flowers typical of the genus. Coast amaranth is assessed as Extinct in the Wild by the IUCN, as it has not been reliably documented from wild populations since the mid-20th century; the last confirmed collections date to the 1960s. The species' decline and likely extinction resulted from intense human pressure on Atlantic coastal habitats through shoreline development, beach stabilisation, vehicular traffic on beaches, and increased storm frequency disrupting pioneer dune vegetation. It is federally listed as Threatened in the United States, though this listing predates confirmed extinction in the wild. A small number of ex-situ accessions may exist in botanical garden collections. Genetic material and seed banking efforts represent the only remaining conservation options for this critically reduced species.

Coast Barnyard Grass

Coast barnyard grass (Echinochloa walteri) is a robust annual grass in the family Poaceae, native to wetlands and coastal marshes of eastern North America, from southern Canada south through the United States. It grows in tidal fresh marshes, brackish marshes, pond margins, wet roadsides, and floodplain habitats, where it can form dense stands exceeding 2 metres in height. The genus Echinochloa is widespread globally and includes several species of agricultural importance, both as crops and weeds. Coast barnyard grass is distinguished by its long, bristle-tipped spikelets and preference for wetland edges. It produces abundant seeds that are consumed by waterfowl including ducks, rails, and sparrows, making stands of this species ecologically valuable in coastal wetland systems. The species tolerates seasonal flooding, fluctuating salinity, and disturbed conditions. Its IUCN status is Least Concern, reflecting its broad distribution across eastern North America and its capacity to colonise disturbed wetland habitats rapidly. While not an invasive species outside its native range, it is sometimes managed in wetland restoration projects to prevent monoculture dominance.