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A Treefree Botanical of Plant Fibers

Bamboo (Bambusa species) is a grass. It is the second most widely used non-wood fiber on the planet (six percent of global plant fiber production), whose bio-attributes just about equal those of pine. Bamboo has become the main non-wood fiber in India, Thailand, and China. (In Brazil the main one is sisal and in Argentina it is bagasse.) Like hemp, bamboo is easy to cultivate and is well known to farmers. Its wondrous versatility in building construction forces bamboo paper lovers to compete with builders for the stems. Not all bamboos are equal. Some have a low fiber content and low yield rate, but there are both warm temperate and tropical species that can become paper yielders.

The Environmental Bamboo Foundation: Ubud, Bali, Indonesia; 62-361/974-02, fax 62-361/974-029; ebfbali@denpasar.wasantara.net.id.

Design and marketing of bamboo products; education and training in all aspects of bamboo production, from planting to marketing; and bamboo based agroforestry and watershed rehabilitation.

Esparto grass (Stipa tanacissima). From southern Spain and northern Africa, esparto grass is used for book papers and by specialty papermakers. The paper has premium formation, smoothness, and ink gloss. Best known for its porosity, the esparto leaf is a cylindrical, rolled-sheath leaf with strong dimensional stability. With a finer fiber density of 15 million fibers per gram — the highest of any paper pulp, and twenty percent more dense than eucalyptus — a little esparto grass can go a long way. Its short fibers can best be extracted by chemically dissolving the lignin (the glue that must be "dissolved" to free up the individual fibers) and re-moving the silica.

Groups of nomadic Bedouin women harvest esparto grass, while the men bundle the grassy stalks. The rootstock remains. The grass could be harvested yearly but it isn't, because the tribes are nomadic and there's so much of it. Camels transport the grass across the desert to a collection area. It is left to dry in the intense sun for six months. This labor-intensive process provides much-needed jobs, supplemental income, and high retail prices.

Flax (Linum usitatissium). The bast fiber (the outer layers of the stem) of textile flax is the source of elegant linen. Linen rags, cuttings, and threads have been used as the feedstock for papermaking for two thousand (or more) years. More recently the straw (whole stem) from linseed oil flax (flax cultivated for its seed) has been used for the manufacture of cigarette and other high-quality papers. Its high tear and tensile strength is superior to wood pulps. Like hemp and bamboo, flax yields multiple products. Paper has been a lower-value end product.

Fiber flax does best in temperate climates. It is more fickle than oilseed flax, and originally grew in areas with cool, moist springs, moderate summers, and rich soil (Belgium and Ireland). In 1843, Sarah Damon Owen brought flax seed west by ox cart from Kentucky, and was amazed that the fiber flax did so well. The flax industry boomed in Oregon, especially during World War II, when European nations stopped exporting.

International Linen Association: c/o Gerli & Co., New York, NY; 212/685-0424. Western European linen weavers and flax processors. Quarterly newsletter: Linen Today.

Hemp (Cannabis sativa). Ah! Infamous hemp. To be grown for THC or good fiber for textiles and ropes and maybe, in the future, plastic and hundreds of other co-products. They say it's hard to breed for both fiber and fun. Male plants are best for fiber, the virgin females for psychoactivity. Marijuana is cosmopolitan, but fiber hemp grows mostly in Europe (Hungary, Ukraine, and smaller amounts in France, Spain, and the UK) and south Asia. Despite rekindled interest, fiber hemp cultivation has been in long decline with shorter-term peaks during the world wars.

Easy to cultivate, the high-yield bast fiber is one of the longest of the non-wood fibers. It is superior to wood pulps and makes an ideal additive to recycled paper pulps to improve strength. Hemp paper is tough and durable and can be finished to a creamy, desirable sheet with the addition of some shorter, softer fiber such as esparto or cotton. About 0.005 percent of the world's paper (by volume) is hemp. Hemp fiber forms the sheeting for the Gutenberg Bible and the Declaration of Independence. In 1575, in the New World, at the first paper mill outside Mexico City, a composite of hemp and cotton rags was the pulp of choice. US hemp paper production began in 1690. It was against the law for Colonial American farmers not to grow fiber hemp. Hemp was extracted by retting (soaking to separate the fiber). During the American Colonial period, masters forced slaves to enter retting basins (even in winter) as the humanoid mechanical separators. So many died of pneumonia that slave-retting became illegal. The whole stalk (bast plus the shorter inner fibers) cannot compete with wood pulp under present market conditions: hemp costs two-and-a-half times more per ton. A new chemi-mechanical process that replaces older, purely chemical processes, may lower costs and help hemp grab a share of the higher-quality printing- and writing-grade paper market.

Most "modern" nations prohibit fiber hemp cultivation. The DEA requires high fences with concertina wire and all-night lighting which penalizes hemp growers. Legal repression has given hemp fiber glamour and a larger market niche. Wearing hemp is also a bumper sticker saying, "Question Authority." Two hundred firms sell hemp products with a projected legal market of $15 to $30 billion per year. Kentucky (looking for tobacco substitutes), Canada, Ukraine, Germany, and the Netherlands are all investigating markets. So far hemp has been labor-intensive. Mechanization of this unfamiliar (yet so familiar) crop needs research and development funds.

Hemp Industries Association: Chandler Heights, AZ; 602/988-9355. Best American access.

Abaca or Manila Hemp (Musa textilis). This leaf fiber, a member of the banana family, makes an extremely strong pulp with a high tear and tensile strength. Abaca is used for marine cordage, Japanese shoji screens, abrasive backing papers, and tea bags. It has potential for paper currency, Bibles, and cigarette papers. No fiber of equal strength and pliancy has been found. Grown in the Philippines by small landholders, its present drawbacks are low yield, high costs, and limited potential for a wider market as a low-end paper product. All manila hemp ropes should be recycled into paper.

Kenaf (Hibiscus cannabis) is considered the latest plant fiber to enter the treefree paper competition. The long bast fibers (similar to flax and hemp, and equivalent to pine) produce porous, high-strength paper with increased opacity and lowered sheet thickness. Definitely superior to wood fibers, kenaf can help reinforce the broken and short fibers of multiply-recycled waste paper. Kenaf yields many products and has been used as fuel, animal bedding, oil absorbent, and particle board for wall paneling.

The USDA started kenaf research thirty years ago. In 1981, the US International Paper Mill carried out a commercial-scale newsprint run that demonstrated the feasibility of a kenaf-based publication. But the wood pulp industry has resisted retooling the mills. For a planned 35,000-acre kenaf operation in Texas that could significantly wedge into the paper market, $360 million had to be raised for a new mill and harvesting equipment. Australia seriously considered kenaf for newsprint but could not arrange the financing and the income security that farmers required before they dared switch to another crop. A similar attempt failed in Thailand.

Less vulnerable to climatic whims and pests, kenaf needs lower inputs and management compared to other bioregional crops. This cotton/okra relative zooms from seed to fifteen feet in as little as five months, with low resins and silica — both favorable price considerations. Kenaf's drawback is its seasonality, requiring storage. Storage can lead to losses from fungi and rot, and complicates milling. Mills want an even flow of material for maximum efficiency.

Originally from the East Indies, kenaf (an annual) is now grown for paper fiber in Texas, Thailand, and China. Kenaf can be used to fabricate tissue paper, paperboard, or roofing felt. Texas produces kenaf interior moldings for cars. Start-up processing plants in California, Louisiana, and New Mexico will make a major attempt to enter the paper market. Prices remain ten to fifteen percent higher than premium recycled papers.

International Kenaf Association: Ladonia, TX; 903/367-7216.

Cotton (gossypium species), the premier textile fiber, enters the paper market as rags, textile scraps, and linters. Linters are a residue, the short fibers that adhere to the seed after ginning. These fibers can be cut from the seed in a series of passes through cutting blades ("first-cut linters," "mill run," "second-cut linters," etc.). Scraps are the major source of non-wood fibers for paper in the United States (about 0.3 percent of all paper pulp). Cotton produces a very high-quality paper, but has high production costs. It has a well-established market niche.

Cotton does best in warm temperate or tropical climates. The soft, fleecy fiber has been cultivated for 5,000 years. It is loved for, among other qualities, its washability— tougher than rayon, stronger wet than dry. Cotton is also moth-free, has great wickability, and a porous coolness. Synthetics stole part of the cotton market because cotton has low drapeability, wrinkles easily, shrinks, mildews, stains with sweat, and bleaches in sunlight.

Bagasse ( Saccharum officinarum), another agricultural residue, is the crushed stalks of sugarcane after the sugar has been extracted. Sugarcane is a grass with high fiber yield, but its short fibers (closer to hardwoods or eucalyptus) and high lignin and silica content increase pulping costs. But India, Mexico, Indonesia, Thailand, Colom-bia, Brazil, Argentina, and South Africa all use bagasse for pulp production because of its fine newsprint qualities. Forty-five percent of all Mexican pulp comes from bagasse. Bagasse accounts for 12 percent of world production of non-wood fibers.

In the 1950s, the US led the world in designing the tools for bagasse pulping. Now, Cuba leads the way. The Cuba-9 Experimental Center studies the application of high-yield bagasse to small-scale pulp mills. The Cubans search for maximum efficiency: a more energy-efficient sugar mill that uses surplus bagasse for fuel; a pulp/paper mill with a low-cost pulping process; animal feed from "waste," and other by-products. Bagasse-based paper pulp competes with other uses such as hardboard and insulation board. Since sugarcane waste is also used for a fuel at sugar mills, a balance must be struck between energy and pulp. In India, sugar mills must be linked to paper mills by law which, at times, stimulates exports of coal to compensate for fuel losses.

Cereal crop straw is the leading non-wood fiber on the planet (forty-seven percent of global non-wood production). Wheat, rye, barley, oats, and rice offer a large straw supply and supplemental income for farmers in the production of low grade paper. China and India are leading recyclers. Straw has good printing qualities despite its short fiber length, which resembles hardwoods more than pines. Drawbacks include high silica content, low cellulose, weak fibers, and high transport costs compared to value. Straw pulps are always mixed with other fibers.

Straw as paper pulp competes with straw as a feedstock in other industries, e.g., straw-bale houses, agriboards, feed supplements, compost, "log" pellets, and chemicals manufacturing. Farmers cannot harvest all their straw without risking lowered soil fertility or erosion. In the US, Ninety percent remains to be plowed back into the soil and to control erosion. In other regions, where straw is burned to clear the fields, the straw pulp alternative both increases income and lowers greenhouse gas emissions. New genetic short-stemmed wheat varieties have hurt the market for straw pulps and agriboard.

Ramie (Boehmeria nivea). Also called China Grass or filasse, ramie is a member of the nettle family. It is the plant that saves the princess condemned to weave nettles into coats of mail in "The Swan," a Hans Christian Andersen fairy tale. This lustrous and super-smooth fiber is difficult to extract and clean. Used for high-class underwear and special threads as well as fancy papers, ramie awaits a techno-breakthrough, cheap labor, or more princesses to lower costs. Native to tropical Asia.

Jute (Corchorus species) has very long, pale yellow fibers that are not particularly strong but important as a recycled paper fiber. Jute is widely employed for gunny sacks, burlap, twine, carpet, curtains, and more. The butt ends and waste scraps from jute rope and sacking join other fibers in paper production.

Burlap and Jute Association: c/o Malcolm E. Martin; New York, NY; 212/408-1040;fax 212/541-5369. Importers and brokers.

Other fibers

Not yet for the big time, other paper fibers have special importance.

Reeds of all types enter the paper market in China, and to a smaller extent in Europe. They offer a free by-product for constructed wetland sewage treatment.

Cornstalks, which comprise thirty percent of all US plant waste fiber, have not been incorporated into paper.

China jute or Indian Mallow (Abutilon Theophrasti) is a lot like jute and now grows weed-like in the US. Adding it to paper would generate revenues from weed-control.

Paper mulberry bark with its soft, lustrous fibers has been used in Japan for paper lanterns, umbrellas, and writing paper.

So-called rice paper comes from other plants, not rice: Tetrapanax payriferum, Edgeworthia tomentosa, and Wickstroemia canescens all transform into elegant fibrous sheets.

Papyrus, the root word of "paper," is the flattened interior of the plant's stem. India and Africa still produce small amounts. Papyrus paper is not what we call paper today (separated fibers reconstituted as sheets).

Sisal hemp or maguey (Agave cantala) grows on arid soils worldwide, with superior tear and tensile strength compared to wood. Because it does not displace important crops and can switch from paper to hard fiber cordage depending on price, its bright white sheets (requiring little bleach) make it a prime candidate for a pine/sisal combo paper.