Chenopodium macrospermum* (Large-seeded Goosefoot) is a weedy herbaceous plant, associated with disturbed and saline soils, including beaches and salt marshes. It is native to South and Central America, and introduced to the West Coast from Mexico. It grows up to 600 mm tall. It was collected in 1890 in Seattle, and 1923, on San Francisco Bay, and is widely distributed on the California coast, and is reported from several counties around Puget Sound. Species-level herbarium records are not available online for this species in Oregon, because of its uncertain taxonomy, but it occurs there.
* The taxonomy of the genus Chenopodium and the family Chenopodiaceae has been drastically revised. The family is now considered a subfamily of Amarnanthaceae. The current name for this species is Oxybasis macrosperma ssp. salsa ((Phil.) Uotila 2022, but this name is not yet reflected in US sources (Flora of North America, USDA Plants database, etc.). (Uotila 2022, Royal Botanic Gardens: Kew (2024), Plants of the World Online. https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:419097-1)