Hemp Rope Basics
Hemp is made from a sativa variety of the Cannabis genus of plants. The plants are fast-growing and can reach more than 15 feet high. The fibers used to make hemp rope are called "bast," the part of the plant that grows underneath the outer layer of bark and surrounds the inner stalk. The fibers are very strong and long, running the length of the plant. Multiple individual hemp fibers are braided or twisted together to form a hemp rope.
History
Hemp rope was used in China as far back as 2,800 B.C. Industrial hemp was once widely grown all over the world as a source for many products as well as rope. Ropes have been used by humans since prehistoric times for various needs, including carrying, climbing, hunting and fishing, lifting, seafaring, construction, basket making and sports. Hemp ropes used for seafaring had to be tarred to prevent rotting. As manila, which does not need to be tarred, became more widely available and increasingly popular for rope making, hemp ropes became less common.
Advantages of Hemp Rope
Hemp fibers make good ropes because they are strong, durable, resistant to mold and ultraviolet light. The manufacture of hemp ropes is more environmentally friendly than the manufacture of synthetic ropes. Hemp is a fast-growing, high-yield crop that does not require the use of pesticides or other chemicals. In contrast, synthetic rope is made from oil-based fibers, so its production consumes nonrenewable fossil fuels. Because hemp rope is made from natural fibers, it is completely biodegradable, unlike synthetic rope which can remain in the ocean or the earth for centuries without breaking down, leaking chemicals into the earth and causing hazards to marine life.
Disadvantages of Hemp Rope
Hemp ropes used in the maritime industry have to be covered with tar to prevent them from rotting. This is because hemp ropes that have dried on the outside tend to trap moisture within the core of the rope, causing rotting and breakage. The ends of a hemp rope have to be bound, otherwise they will fray. The lifespan of a hemp rope is around five years.
Politics and Hemp Rope
The production of industrial hemp is still illegal in the United States because it is a member of the cannabis plant family and U.S. law does not distinguish industrial hemp from any other form of cannabis. An exception to this was during World War II, when hemp rope production was officially encouraged in the United States, despite still remaining illegal. Hemp was needed for ropes for military use to replace manila sourced from Japanese-controlled markets.