Fibres derived from the bark of annual plants, such as flax, hemp, kenaf or jute; main characteristic of bast fibre is long length.
Bast fibre (fiber) or skin fibre is fibre collected from the Phloem (the "inner bark" or the skin) or bast surrounding the stem of a certain mainly dicotyledonic plant. Most of the technically important bast fibers are obtained from herbs cultivated in agriculture, as for instance flax, hemp or rhamie, but also bast fibers from wild plants, as stinging nettle, and trees as the lime tree, have been used to some extent. Since the valuable fibers are located in the phloem, they must often be separated from the xylem material ("woody core"), and sometimes also from epidermis.