Linum lewisii Linum lewisii Linum lewisii ("Linum perenne" var. "lewisii") (Lewis flax, blue flax or prairie flax) is a perennial plant in the family Linaceae, native to western North America from Alaska south to Baja California, and from the Pacific Coast east to the Mississippi River (USDA Plant Profile: "Linum lewisii"). It grows on ridges and dry slopes, from sea level in the north up to in the Sierra Nevada. It is a slender herbaceous plant growing to 80 cm tall, with spirally arranged narrow lanceolate leaves 1–2 cm long. The flowers are pale blue or lavender to white, often veined in
Flax contains small amounts of cyanogenic glycoside; these are nontoxic when consumed in typical amounts, but may be toxic when consumed in large quantities of such staple foods such as cassava. Typical concentrations (for example, 0.48% in a sample of defatted dehusked flaxseed meal) can be removed by special processing. The soils most suitable for flax, besides the alluvial kind, are deep loams containing a large proportion of organic matter. Flax is often found growing just above the waterline in cranberry bogs. Heavy clays are unsuitable, as are soils of a gravelly or dry sandy nature. Farming flax requires few fertilizers