- Name also: Iron-root, Spear Saltbush, Spear Orach, Spreading Orach
- Family: Amaranth Family – Amaranthaceae
(formerly Goosefoot Family – Chenopodiaceae)
- Growing form: Annual herb.
- Height: 30–60 cm (12–25 in.).
- Flower: Male flower: perianth calyx-like, regular, ca. 1 mm (0.04 in.) across, perianth-segments 5. Stamens 5. Female flower: lacks perianth, enclosed by 2 erect, mealy bracts, usu. stalkless, 2–5 mm (0.08–0.2 in.) long, having 2 lateral and 0–2 central teeth. Carpels fused, gynoecium 2-styled.
- Leaves: Lower leaves opposite, upper alternate. Blade narrowly elliptic–ovate–broadly ovate, usu. hairless. Margins entire apart from 2 basal teeth, or shallowly toothed.
- Fruit: Achene enclosed by and united with 2 erect bracteoles.
- Habitat: Yards, gardens, fields, rubbish tips, and rarely shores.
- Flowering time: July–August.
Different oraches (Atriplex spp.) are difficult to distinguish between. Oraches are very similar to species of genus Chenopodium from which they can, however, be separated by that Atriplex species have unisexual flowers (they are monoecious or rarely dioecious) and characteristic fruit-enclosing bracteoles. The appearance of these bracteoles is also among the best distinguishing characters within genus Atriplex. Common orache is annual and, unlike other Finnish oraches, typically associated with human influence. It requires almost neutral, nitrogen-rich soil.
Common orache is easily confused with its closest relative, grassleaf orache (A. littoralis), but can be distinguished by the single pair of marginal teeth on the fruit-enclosing bracts. The margins of the bracts of grass-leaved orache are irregularly toothed throughout. Common orache was formerly used as a vegetable.