| Fiber Plants  What are natural plant fibers?
Natural plant fiber in this context include fibrous materials extracted from both plant bark (bast fiber) and core. Chemical components of these fibers are mainly cellulose, hemicellulose, pectin, and lignin, which are important materials for industrial applications. These fibrous plants include, but no limited to, jute (Corchorus olitorius and Corchorus capsularis), kenaf (Hibiscus cannabinus), flax (Linum usitatissimum), industrial hemp, and ramie (Boehmeria nivea). Other fibrous materials extracted from leaves and seeds are also widely used. These natural fibers have become raw materials of many industries while synthetic fiber is quickly losing its competitive advantages. These old crops, which have been cultivated for thoudand years, play an important role in developing toward a green industry.  Production of natural fibers
Agricultural production of bast fiber crop, jute, kenaf, hemp is distributed in different geographical regions. Jute and kenaf are warm season annual and cultivated almost exclusively in Southeast and East Asian countries like India, Bangladesh, China, Thailand, Indonesia, Viet Nam, and Nepal. Hemp grows mostly in mild temperate climates. Countries producing hemp include mainly Russia, Australia, Austria, Canada, China, Great Britain, North Korea, Hungary, Romania, Poland, France, and Italy. It is illegal to produce hemp commercially in the United States, although some states allow hemp cultivation for research purposes. Flax grows well in temperate climates. Countries producing flax include Canada, China, India, United States, northern Europe and Russia.  Products made from plant fibers
Natural plant fibers are being increasingly used in manufacturing industrial products becasue of their renewable and biodegradable natures. Natural fiber-based products have been seen in industries like automotive, paper, construction, environmental cleaning, transforpation, and food, etc. More information can be found at Green Fiber Net. Following list some examples of products made from natual plant fibers: |
| | | About Kenaf What is kenaf?
Kenaf (Hibiscus cannabinus L.) is a warm season, short-day, annual herbaceous plant originated from west Africa which has been cultivated since around 4000 B.C. Kenaf belongs to the Malvaceae, a family notable for both its economic and horticultural importance. In different parts of the world, kenaf has many other names such as mesta (India, Bengal), stockroot (south Africa), Java jute (Indonesia), and ambari (Taiwan), etc. Kenaf has a high growth rate, rising to heights of 12-18 feet in about 4-5 month. Its yield of 6-10 tons (new varieties may reach 12 ton) of dry weight per acre per year are generally 3-5 times greater than the yield for Southern pine trees which can take from 7 years to reach harvestable size. The fibers from kenaf can be classified into bast fibers which is about 35% the stalk dry weight and core fibers which comprises about 65% of the stalk dry weight. Kenaf fibers can be used in making many agricultural and industrial applications like paper pulp, thermoplastic, composite, non-woven, geotextile, pot mix, agricultural mulch and film, fabrics, industrial absorbent, etc. All these applications contribute to environmental protection. For more information about kenaf, please see the selected papers. Kenaf Cultivation
In the late 1950s, substantial research was conducted on kenaf because of a research program initiated by the United States Department of Agriculture to evaluate a number of crops for possible paper pulp production. Kenaf was identified as the most promising crop for pulp and paper making. Therefore, abundant of data are available for kenaf in agricultural production, cultivation techniques, field management, processing, harvesting, transporting, storage, and cropping systems.
Kenaf grows in tropical and subtropical warm climates. The optimum temperature for kenaf growth is around 25 ºC. The effective accumulated temperature need to be above 3000 ºC for harvesting kenaf fibers and above 3300 ºC for harvesting kenaf seeds. Kenaf sowing is normally conducted by broadcasting at a seeding rate of 22.5 – 30 kg per hectare at soil depth of 2 cm. Plant population is an important factor affecting fiber yield and fiber quality. A study showed that a yield of 10.2 ton per hectare can be obtained at plant population of 270,000-300,000 per hectare.
Kenaf's primary root system can grow as deep as two meters in the soils. Like jute, kenaf also develops adventitious roots on the base of stems during waterlogging, which allows kenaf to survive prolonged waterlogging. After establishment, kenaf can tolerate waterlogging for a sustainable period of time. Study showed that after growing above 50 cm, kenaf can survive submerged for up to 9 days. All soils are adapted for kenaf cultivation including acid, peat, alluvial, silt loam, sandy loam, clay loam, alkaline and saline soils. Kenaf shows similar tolerance to salinity as cotton and perform better than wheat and corn under salinity condition. Kenaf’s wide ecological adaptability allows it to grow in marginal lands which can not grow food crops. In addition, cultivation of kenaf helps conserve the environments and soil fertility. A study showed that cultivation of one hectare of jute or kenaf will return 3.84 tons biomass to the soils in the form of leaves, roots, and retting waste. Kenaf cultivation does not require lots of agricultural inputs like field management, and use of fertilizers, herbicides, and pesticides.
A good collection of kenaf gemplasm has made it possible for developing a number of kenaf varieties. Breeding efforts have been focused on high biomass and fiber production, improving tolerance to unfavorable environmental conditions like drought, flooding, salinity, acidity, and root-knot nematode disease. Similar to jute, early flowering is a problem in kenaf production. Developing photo-insensitive variety has been on high breeding agenda for kenaf. Fujian Agricultural University has successfully obtained a variety with delayed flowering through sending the seeds to the space. Fuhong 952 is another variety with both high yield and fiber quality developed in the same institute. Other commercially cultivated varieties include: Everglades 4l, Tainung 2, and Cuba 2032. |
| | Articles and References on Kenaf and Allied Fibers |
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