Allium platycaule is a species of wild onion known as broad stemmed onion or flat-stem onion. It is native to northeastern California, south-central Oregon (Lake County) and northwestern Nevada (Washoe and Humboldt Counties). It is found on slopes of elevations of 1500–2500 m.

Allium platycaule grows from a gray bulb 2 to 3 cm (3⁄4 to 1 1⁄4 in) wide. Scape is thin and strongly flattened, up to 25 cm (9 3⁄4 in) long but rarely more than 7 mm (1⁄4 in) across. It may be thicker along the midrib and much narrower along the sides. The long, flat leaves are sickle-shaped. Atop the stem is an umbel which may have as many as 90 flowers in it. Each flower may be up to a centimeter and a half wide but the tepals are quite narrow so as to be almost threadlike. The inflorescence therefore may appear be a dense ball of filaments. The flowers are generally bright pink to magenta with yellow anthers.

Source
Wikipedia