Mandioca or cassada is likewise cultivated in great quantity. Every part of this plant is useful; the leaves and stalks are eaten by the horses, and the roots are ground into a pulp, which, when pressed dry and baked, forms the farinha, the principal article of sustenance in the Brazils. It is a curious, though well-known fact, that the juice of this most nutritious plant is highly poisonous."


The same plant is grown in many part of sub saharian africa, (and called foo-foo, and various other names. the root is poisonous, too, and is only edible after it has been soaked in water, then dried, then ground (or mashes) and then soaked and cooked. the plant is rich n cyanide, and even with the treatment, it still is rich in cyanide, and it is a very poor quality food.

still, its a major food for millions of people.