The cultivation of hemp for fiber has been recorded as far back as 2800 BC in China, and it spread throughout Europe during the Middle Ages. Hemp, or industrial hemp, is a botanical class of Cannabis sativa cultivars cultivated specifically for industrial or medicinal use. It is one of the fastest growing plants on Earth and was one of the first plants to be spun into usable fiber 50,000 years ago. Hemp can be refined into a variety of commercial items, such as paper, ropes, textiles, clothing, biodegradable plastics, paint, insulation, biofuel, food and animal feed.
Although both chemotype I cannabis and hemp (types II, III, IV, V) are Cannabis sativa and contain the psychoactive component tetrahydrocannabinol (THC), they represent different groups of cultivars, usually with unique phytochemical compositions and uses. Hemp generally has lower concentrations of total THC and may have higher concentrations of cannabidiol (CBD), potentially mitigating the psychoactive effects of THC. The legality of hemp varies greatly from country to country. The etymology of hemp is uncertain; it seems that there is no common Proto-Indo-European source for the various forms of the word.
The Greek term alphaßabeta (kánnabis) is the oldest attested form, which may have been taken from an earlier Scythian or Thracian word. Then it seems to have been borrowed from Latin and, separately, from Slavonic and from there to the Baltic, Finnish and Germanic languages. In those languages, hemp can refer to varieties of narcotic cannabis or industrial fiber hemp. Hemp can be used to manufacture a wide range of products such as thermal insulation blocks for interiors, roof acoustic insulation, concrete blocks made with hemp in France, sustainable construction in practice houses that used hemp as one of its building materials, hemp plastic interior box car glove box hemp plastic column, car and car.
However, hemp has had difficulty competing with paper from trees or recycled newsprint. Only the outer part of the stem is mainly composed of fibers that are suitable for paper production. Numerous attempts have been made to develop machines that efficiently and economically separate useful fibers from less useful fibers but none have been completely successful. This has meant that hemp paper remains expensive compared to paper from trees.
Hemp jewelry is also popular; it is made by tying hemp strings together through the practice of macrame. Hemp jewelry includes bracelets, necklaces, anklets, rings, watches and other ornaments. Some jewelry has pearls made of crystals, glass, stone, wood and bones. The dense growth of hemp helps kill weeds even thistle. The separation of wool and lyber fibers is known as decortication.
Traditionally this was done by hand but now mechanical technology has evolved to separate the fiber from the core by shredding rollers and brush rollers or by milling with a hammer. Recently a new high-speed kinematic decoration has been created capable of separating hemp into three streams: lyber fiber wool and green microfiber. The plots of small producers are usually harvested by hand but mechanical harvesting is now common using specially adapted cutters-binders or simpler cutters. The cut hemp is placed in strips to dry for up to four days traditionally this was followed by decay either by water (hemp floats in water) or by dew (hemp remains in the soil and is affected by moisture in the dew and by the action of mold and bacteria). Hemp plants can be vulnerable to several pathogens such as bacteria fungi nematodes viruses and other various pathogens. These diseases rarely affect the yield of a hemp field so hemp production is not traditionally dependent on the use of pesticides. The United Kingdom Germany Canada United States and Germany among many others process hemp seeds into a growing range of food and cosmetic products many traditional producing countries continue to produce textile-grade fiber. The industrial production of hemp seed harvesting machine in France has recently been revived due to its many uses such as insulation blocks roof acoustic insulation concrete blocks made with hemp in France sustainable construction in practice houses that used hemp as one of its building materials hemp plastic interior box car glove box hemp plastic column car car paper ropes textiles clothing biodegradable plastics paint insulation biofuel food animal feed jewelry bracelets necklaces anklets rings watches ornaments.