- Latin synonym: Chenopodium polyspermum
- Name also: All-seed, Manyseeded Goosefoot, Manyseed Goosefoot
- Family: Amaranth family – Amaranthaceae
(formerly Goosefoot Family – Chenopodiaceae)
- Growing form: Annual herb.
- Height: 10–50 cm (4–20 in.). Stem ascending–erect, scarcely-branched, reddish, quadrangular.
- Flower: Regular (actinomorphic), ca. 1,5 mm (0.06 in.) across. Perianth consists of 5 green, hairless segments that are united at the base. Flowers almost stalkless, very small, borne in dense clusters. Stamens 1–3. Carpels fused, gynoecium 2-styled.
- Leaves: Alternate. Ovate to oblong, stalked, hairless, and with entire margins. Base of blade wedge-shaped or rounded.
- Fruit: Thin-walled, black or reddish achene.
- Habitat: Gardens, fields, rubbish tips, waste ground, shores.
- Flowering time: July–September.
The species within subfamily Chenopodioideae are difficult to distinguish between. They often include several varieties whose identification usually requires the use of a microscope. One of the important distinguishing characters is the texture of the seed-coat. The genus is easily confused with oraches (Atriplex spp.). However, the latter have unisexual flowers and characteristic fruit-enclosing bracts.
Many-seeded goosefoot, also known as all-seed, usually has a lax stem with an ascending top. It is often (at least when older) reddish and quadrangular in cross-section. Many-seeded goosefoot, like many of its relatives, is an annual favoured by traditional farming practices and other human activities. It is usually encountered in fertilised fields and on other nitrogen-rich sites. Also clayey and rocky shores are suitable habitats for this plant.
Many-seeded goosefoot can be distinguished from very common fat hen (C. album) by that it lacks hairs and has leaves with entire margins.