plant fibres

Plant fibres are long, stretched, thick-walled cells whose composition is principally cellulose. This macromolecule, itself comprised of simple sugars, strengthens the cell walls of the fibre by forming itself in layers. Individual fibres are grouped together in longer strands, known as fibrebundles and are glued together with pectin, sometimes also with lignin. Their unique design and strengthened cell structure differentiate useful natrual fibres from the many other fibres found in the plant kingdom. In general, natural fibres can be grouped into two categories: soft fibres and hard fibres.

Most soft fibres come from the bast portion of the plant. Also called the pfloem, the bast lies directly under the outer bark or skin. Here the transport of the products of photosynthese and the development of stabilizing structures take place. Through the process of retting, the bast is removed from the stems. Hemp, Flax, Jute and Ramie are soft fibres.

Hard fibres are comprised not only of the phloem but also partly of the hardened wood core of the plant, the Xylem. The hardness in the the plant's fibres is caused by the deposit of lignin in the cell walls. Hard fibres generally come from the leaves of monocot (single seed-leaf) species, for example Sisal agave, fibre banana and diverse palms.