Flax health of linseed oil. Eventually, Flanders became the major center of the linen industry in the European Middle Ages. In North America, flax was introduced by the colonists and it flourished there, but by the early 20th century, cheap cotton and rising farm wages had caused production of flax to become concentrated in northern Russia, which came to provide 90% of the world's output. Since then, flax has lost its importance as a commercial crop, due to the easy availability of more durable fibres. Flax is grown for its seeds, which can be ground into a meal or turned into
Vavilovian mimicry that lives with flax". Weeding of the adult plant is impractical; instead they are separated based on properties of the seed. This is done by a winnowing machine, which in this case acts as an inanimate signal receiver. Seeds that are thrown the same distance as flax seeds have thus been selected for, making it near impossible to separate the seeds of these two species. Another example is rye ("Secale cereale"), a grass which is derived from wild rye ("Secale montanum"), a widely distributed Mediterranean species. Rye was originally just a weed growing with wheat and barley, but came under