Hemp or Cannabis sativa is probably the oldest non-food crop of all. It has been cultivated in Asia to produce ropes, fabrics and oil-seed since Neolithic times. It spread as far as Europe by 1500 BC but took another 2000 years before it became a significant fibre crop in the continent.
The narcotic properties of the plant have been enjoyed in India for over 3000 years but perhaps because the drug content of the crop is dramatically reduced in cooler temperatures, this was not appreciated in Europe possibly until as late as the eighteenth century. Even so for many years hemp was the most traded commodity on earth. The Great British Empire whose navy dominated the Seven Seas was dependent upon hemp canvas sails and hemp fibre ropes, (the word canvas being derived from cannabis). Without hemp Columbus would not have discovered the Americas, and American troops would have gone naked into battle during the Second World War. In spite of its great and glorious past cannabis is now a minor crop on the world stage in terms of fibre, while as a recreational drug it is widely illegal and its possession is even punishable by death in some places.
Botanically, cannabis is in a rather small family along with the related hop plant. As with hops, cannabis is usually found as separate sexed plants, with the female of the species being favoured. Genetic control over gender in cannabis is highly complex, but with certain changes in day length and temperature it is possible for male plants to produce female flowers. The reverse sex change operation from female to male can be performed by a simple act of decapitation!
Female plants have been considered to produce the best quality fibre and to have more of a narcotic effect than do males and of course because males do not produce seeds they are of little value in producing oil. For this reason over the years hermaphrodite plants have tended to be selected for, along with different varieties for fibre and recreational uses. The complexity of the different sexual forms of cannabis has resulted in many different terms being used to describe the various products derived from these different plants. Thus the words ganja and marijuana, although widely used to refer to the entire plant of either sex are more technically terms for the flowering tops of female plants. This has the potential to make life very interesting in a court of law, because since 1913, the cultivation, importation, possession or use of ganja has been illegal in Jamaica. The original use of the word ganja in Jamaican law was designed to differentiate its use as a drug from hemp grown for fibre. However, within the strict definition of ganja it would therefore not be illegal to cultivate, import, possess or use male cannabis plants. It is technically almost impossible to determine the gender of a fragment of hemp leaf material. This fact could be used to mount a spirited defence, as males are as common as females, so technically only half the crop is illegal. However, in spite of the reality of the widespread recreational use of ganja on the island and pressure from Rastafarians to legalise it on religious grounds, over the years the Jamaican laws on cannabis use have been tightened because of pressure from the United States. This happened first following the passing of the 1937 Marijuana Tax Act in the US. The newspaper magnet William Randolph Hearst was very active in lobbying for this legislation and campaigned against the evils of cannabis use. Perhaps his motives were not so innocent, because imposing restrictions on hemp cultivation and hence hemp paper manufacture greatly benefited Hearst’s own financial interests in the timber pulp and newsprint industries.
There is another beautiful irony in American imposing its will on the legislation governing ganja use in the independent nation of Jamaica. In 1776 when Thomas Jefferson wrote the Declaration of American Independence he did so, on hemp paper. Furthermore this paper could have been grown on George Washington’s hemp plantation and made in Benjamin Franklin’s hemp paper mill.