Ropes have been made out of natural fibers since before recorded history, and they still have a place in modern production. Fibers of natural rope are partly plant cellulose, and their stiffness and limited length give natural rope its somewhat harsh and fuzzy look and feel. Because of their plant origins, natural fiber ropes are susceptible to rot from mold and mildew, and should be stored in a dry location. They can also be damaged by oils, acids, and other solvents. Some ropes are conditioned with chemical additives to make them less susceptible to these agents.

Natural ropes handle well and are good at holding knots. They are often chosen because they are inexpensive and natural in appearance. They are almost always in the form of twisted rope, because that is the only way to group the fibers. An exception is cotton or silk, which has a fine enough structure to be spun at thread size and can be woven.

Fibers Stiff and Soft

The stiffer and rougher fibers of larger ropes are usually made from the leaves of manila and sisal. Manila is darker, stronger, and more expensive then sisal; it weathers better than other natural fiber ropes, but should still be dried before storing, even if it has been chemically treated for protection.

Softer fibers are made from the stems of plants like jute, flax, or hemp. These are seldom used in larger ropes anymore. Jute appears as inexpensive garden twine and in decorative cords, and hemp is often used for small jewelry cord, which gets smoother over time when worn as a bracelet.

Cotton is being replaced by synthetics but still appears as both large and small cordage. It is used in handling farm animals because it is smooth and does not burn skin with repeated rubbings nearly as much as other rope materials. Both cotton and silk are used in small sizes for decorative purposes.