PUBLISHED MAY 1996
by Carolyn Moran, Editor & Publisher, Talking Leaves
I have been the editor and publisher of an ecology magazine called Talking Leaves for seven years. As an ecology magazine, we are concerned about the dwindling forest ecosystems worldwide, a substantial portion of which are felled for the pulp and paper industry. When I discovered I did not have to use wood pulp for paper, I decided to switch my magazine to a tree-free alternative.
The first non-wood paper that I tried was imported from China with a 50% hemp and 50% straw content. The paper from China did not live up to the printing industry standards of the western world and continually jammed the web presses. Since I did not want to go back to supporting the use of trees for pulp and paper, I embarked upon a world journey in search of a good quality tree-free paper. When I returned to the United States, I got in touch with the non-wood sector of the pulp and paper industry. They agreed to support my efforts to manufacture a tree-free paper in the US.
I began to discover all the intricacies involved in the production of paper-especially paper that uses alternative sources of fiber. Traditionally paper was made out of plant fibers. At one time practically all corrugated material was made from straw. Because the economics of pulp production have favored wood in the US, use of plant fibers had declined.
Modern technology for production of pulp from non-wood fibers was developed primarily in the US. It was based on extensive research and development programs on bagasse (a sugar cane by-product) pulping which started in the ’50s and continues today. Although used to a limited extent in the US, this technology has spread worldwide. Fortunately this technology can be applied to other non-wood fibers.
Wood pulp prices are steadily on the rise and we are running out of forests. Now is the time to implement solutions. The forests of Chile are being felled for fax paper to satisfy the insatiable demands of the US and Japan. Wheat straw, a waste product of the grass seed industry, is perfectly suitable in making fax paper. There are 1.5 billion tons of agricultural by-products created annually in the world and these by-products are good for papermaking.
The goal is to increase the use of alternative fibers for both pulp and paper and other current wood-based products and to create a demand that will make these products cost competitive. Non-wood plant fibers currently used in producing papermaking pulp include agricultural residues such as bagasse and straws; natural growing plants such as bamboo and grass; and plants grown for their fiber content such as hemp, kenaf, jute, abaca, sisal, and cotton. Almost every known fiber has been tested for pulp and paper production and almost every one results in a product with some desirable properties.
There are many plants that can be used to make pulp and paper. The two most popular fiber plants at present are hemp (Cannabis sativa) and kenaf (Hibiscus cannabis).
Hemp has the ability to grow in a wide range of climates and is grown in many temperate countries. Hemp has played a significant role in the history of papermaking. Although hemp cultivation is illegal today in the United States, it was against the law for farmers not to grow it in Colonial America. The bast fiber (outer layers of the stem) make a strong and durable paper that can be finished into a creamy, desirable sheet with the addition of some shorter, softer fiber such as esparto and cotton.
Kenaf is an annual plant which was originally from the East Indies but is now widespread. The growing season for kenaf is longer than that of hemp and the plant is restricted to warmer climates. The US Department of Agriculture began preliminary research on kenaf as a paper fiber more than 30 years ago. Kenaf and hemp can be used to make a variety of products from tissue to fiber board to roofing felt. The long bast fibers, which are similar to hemp, produce porous, high-strength paper, while blends of short and long fibers produce pulp similar to the hardwood/softwood blends used in many papers.
Esparto is a cut grass that grows in southern Spain and northern Africa. It is an intriguing non-wood source of fiber that specialty papermakers are familiar with. It has the qualities of formation, smoothness, and ink gloss that are required in premium printing papers. It’s best known quality is porosity due to the fact that esparto grass is actually a cylindrical, rolled-sheath leaf with strong dimensional stability. With a fiber density of 15 million per gram-the highest of any paper pulp and 20% denser than eucalyptus-a little esparto goes a long way.
Esparto grass is harvested by the women of the nomadic Bedouin groups in northern Africa. The men handle the bundling chores but the women gather the grassy stalks. Only the blades of grass are harvested leaving the root substructure. The grass could be harvested in the same place every year but it isn’t because there is so much of it and the tribes are nomadic. The grass is transported by camel across the desert to a collection area. It is left to dry in the African sun for six months. This is a labor intensive process providing jobs for a very populated area.
Bamboo is the second most widely-used non-wood fiber on the planet. Like hemp, it is easy to cultivate and well-known to farmers. The fiber length is equivalent to that of pine. There are both warm temperate and tropical species that can be used for paper.
Cotton linters are the short fibers adhering to cotton seed after the operation of ginning (seed removal and cleaning). These fibers are cut from the seed in a series of passes through cutting blades, and are therefore referred to as “first-cut linters,””second-cut linters,””mill run,” etc. Linters are used in the manufacture of cotton fiber content paper which is considered very high quality.
Flax is a bast fiber plant that has been the source of linen for several thousand years. Linen rags, cuttings, threads, etc. have long been used in papermaking. More recently the straw from flax cultivated for seed has been used for the manufacture of cigarette papers and other papers.
The flax industry was once a booming industry in Oregon. The flax fibers were used to make everything from fire hoses to fine linen. Flax was first cultivated in Oregon in 1843 by a woman pioneer who brought seed with her by ox cart from Kentucky. She was amazed by the height and quality of the plants that grew in the Willamette Valley. While oilseed flax plants thrive in a variety of climates, fiber flax is more fickle. For centuries it had grown only in a few locations, primarily European countries such as Belgium and Ireland. In these regions, the springs are
cool and moist, summers moderate, and soils rich. Those were the conditions of the Willamette Valley. By 1870, commercial mills in Lebanon and Albany were churning out products and providing markets for farmers.
The flax industry boomed during World War II, when European nations stopped exporting flax and Oregon became the nation’s sole supplier of flax fiber needed for military supplies.
Abaca is a naturally occurring fiber found in the stem of the abaca plant-a member of the banana family. The fiber is also called manila hemp and is used extensively in the manufacture of marine cordage, abrasive backing papers, tea bags, and other products requiring high tensile strength. It was during WWII that the US supply of manila hemp was cut off and thus our government began a national campaign for the cultivation of industrial hemp for military use during this era.
Bagasse is the crushed stalks of the sugar cane after the sugar has been extracted. Starting in 1989, depressed prices for sugar forced many sugar cane growing countries to look for ways to diversify their industries. The use of bagasse for producing pulp and paper is receiving renewed attention. In Cuba, the Cuba-9 Experimental Center is studying the applications of high-yield bagasse pulping to small-scale mills. The aim is to offer an integrated package consisting of a more energy-efficient sugar mill with surplus bagasse; a pulp and paper mill based on a low-cost high-yield pulping process; plus animal feed and other by-products. The technology developed is used to assist developing nations which wish to make newsprint from bagasse fibers.
Ramie is a plant of the nettle family native to tropical Asia. The bast fiber from the decorticated material is commercially known as China Grass and is used as a textile fiber. It is a potential source of papermaking fibers.
Sisal is a plant native to Central America. The fiber obtained from its leaves is used for hard fiber cordage. The fiber has also been called sisal hemp.
The need to build a sustainable future cannot be denied. Sustainability is a complex issue. It is a step in the right direction to use alternative fibers for pulp and papermaking. However, alternative fibers are generally monocultures and pesticides, chemical fertilizers, and sometimes herbicides are used in their production; therefore a sustainable method of long-term agricultural practices needs to be implemented as well.
Personally, I believe that fiber hemp (cannabis sativa) has the greatest potential to seed sustainability. With hemp you can start from the bottom and introduce the value of sustainable agricultural practices instead of remaining caught in the machine of large scale petrochemical agriculture which is already in place with other fiber plants. It also offers the opportunity of community-based bioregional economics-local production for local needs with economics that stay within the local community.
Carolyn Moran is editor and publisher of Talking Leaves, a global journal of ecology and activism. She is also the owner of the Living Tree Paper Company which produces the first commercial hemp-content tree-free paper in the US. Her paper consists of hemp, esparto grass, agro residues, and post-consumer recycled fiber.