Vegetable Fibers
. Vegetable fibers are predominantly cellulose , which, unlike the protein of animal fibers, resists alkalies. Vegetable fibers resist most organic acids but are destroyed by strong mineral acids. Improper use of most bleaches can also weaken or destroy these fibers. There are four major types of vegetable fibers: seed fibers, which are the soft hairs that surround the seeds of certain plants; bast fibers, the tough fibers that grow between the bark and stem of many dicotyledonous plants (see Dicots ); vascular fibers, the tough fibers found in the leaves and stems of monocotyledons (see Monocots ); and grass-stem fibers. Other fiber types, of limited utility, include strips of leaf skins, such as raffia ; the fiber of fruit cases, such as coir; and palm fibers. Only two seed fibers, cotton and kapok (see Ceiba ), have commercial importance. Cotton fiber, which grows in the seed pod of cotton plants, is the only one that is useful for the manufacture of textiles. Different species of