Lyster H Dewey, Senior Botanist, Bureau of Plant Industry
Hemp Fiber Losing Ground, Despite Its Valuable Qualities
Hemp is one of the oldest of known textile fibers. There is a definite record that the hemp plant (Cannabis Sativa) was cultivated in China for fiber production 27 centuries before the Christian Era. For nearly 5,000 years it has been important and has won an honorable position because of its strength and durability and the well-established fact that it is dependable. Until less than a century ago hemp and flax were the principal fibers of vegetable origin. While flax was the aristocratic fiber for fine linens, laces, and embroideries, hemp was the strong and dependable fiber for ropes, cables, and sails. The name canvas is derived from the Arabic name for hemp. The Pilgrim Fathers at Plymouth and the Cavaliers at Jamestown planted hemp and flax among their earliest crops. The clothing of the men was hempen homespun, and it did not quickly wear out. The famous clipper ships that carried the merchandise on the seven seas until the middle of the last century were outfitted with sails, ropes, cables, halyards, and shrouds all made of hemp fiber. Many of the covered wagons that crossed the plains before 1860 had covers of real canvas.
For many of these uses of former days, hemp has been replaced by other fibers. In some instances fibers have been found that are better adapted for the particular purposes; for some temporary uses cheaper fibers have been found to serve the purpose quite as well; but in many cases hemp has been crowded out for uses where its strength and durability are desirable qualities.
Hemp for marine cordage has been superseded by abaca (Manila hemp) because the abaca ropes, cables, and hawsers are lighter and will float in water and this hard fiber is resistant to injury from salt water without being tarred. Hemp fiber is used in the marlines or twines with which the ends of the larger ropes are bound. The term “hemp rope” has lost its significance for in America ropes are no longer made of hemp.
Cotton, which is adapted to a wider range of uses than other vegetable fibers, has replaced hemp for many purposes, and in most cases advantageously, for it can be spun more easily and with less waste, making smoother and more uniform yarns. Cotton twines, of course, are not as strong or as durable as hemp twines of the same size or weight.
Jute, which was first brought from India to Europe and North America about a century ago, is now used more than all other vegetable fibers combined except cotton. It is the cheapest and most easily spun of any of the soft fibers, and it is well adapted for purposes where strength and durability are of secondary importance but it is the weakest and least durable of the important textile fibers. Jute has replaced hemp for many temporary uses such as covering for cotton bales and packages of merchandise in transit and sacks for coffee, sugar, and grain where the cheaper fiber may give satisfactory service; but the weak and short-lived jute does not give as satisfactory service as the stronger and more durable hemp for twines for tying heavy packages, hop vines that must be exposed to the weather all summer, carpet warp that ought to last many years, or furniture webbing that should last a lifetime.
Owing partly to the resistant character of the fiber itself and partly to the lack of development of special machinery for spinning hemp, this fiber is not spun as efficiently and cheaply as cotton and jute. The average price per pound of scutched hemp fiber is nearly twice the average price of jute and less than the price of cotton, but hemp yarns are more expensive than those of cotton as well as jute.
The uses of hemp have thus been reduced by the competition of cheaper yarns made of other fibers. At the present time water-retted hemp imported from Italy and dew-retted hemp produced in Wisconsin, Illinois, and Kentucky are used for the following purposes:
- Wrapping twines for heavy packages.
- Mattress twine for sewing mattresses.
- Spring twine for tying springs in overstuffed furniture and in box springs.
- Sacking twine for sewing sacks containing sugar, wool, peanuts, stock feed, or fertilizer.
- Bailing twine, similar to sacking twine, for sewing burlap covering on bales and packages.
- Broom twines for sewing brooms.
- Sewing twine for sewing cheesecloth for shade-grown tobacco.
- Hop twine for holding up hop vines in hop yards.
- Ham strings for hanging up hams.
- Tag twines for shipping tags.
- Meter cord for tying diaphrams in gas meters.
- Blocking cord used in blocking men’s hats.
- Webbing yarns which are woven into strong webbing.
- Belting yarns to be woven into belts.
- Marlines for binding the ends of ropes, cables, and hawsers to keep them from fraying.
- Hemp packing or coarse yarn used in packing valve pumps.
- Plumber’s oakum, usually tarred, for packing the joints of pipes.
- Marine oakum, also tarred, for calking the seams of ships and other water craft.
Other fibers are competing with hemp for even this limited list of uses, and for some of these uses increasing proportions of jute are mixed with hemp.
The annual importations of hemp into the United States in the last five years have ranged from only about 1,200 to 2,000 tons, compared with 5,000 to 8,000 tons previous to 1914, and the domestic production amounting to 800 to 1,00 tons per annum is only about one-half that of the years between 1908 and 1913.