From TIM EASTERBROOK; EARL BROWN contributing
May 18, 2009 Ukiah, Mendocino County, North California
An integral aspect of the Eco-Village and a sustainable future will be re-cycling. This is not limited to today’s meaning of separating the tin from the plastic, the green glass from the clear, and the paper from the rest; this is waste separation, re-cycling will take on a deeper and broader meaning as we move into the challenging years ahead.
Waste separation is an aspect of the process of recycling, yet, most importantly in the process is using the end waste product, or products, from one industry to feed a part, or parts, of another; re-using, possibly for reasons other than originally intended; re-manufacturing new materials, or structures from part, or parts, of the waste stream, and reclamation of usable components (oils, water, chemicals, nutrients) from objects and solutions before their final (for us) resting, composting, place.
By building “Zero Waste” into our planning as an ideal to work toward, while understanding we are in a transition phase and unlikely to achieve such a lofty goal quickly, we can open our individual and collective creativity without thinking we have to have all the answers before beginning.
Being in transition means action; something is happening and movement is involved. In Mendocino County we can feel the burden of the past blurring into a questionable future and wonder what we will transition into; a peaceful, sustainable group of interdependent communities living within their means, supporting each other through the lean times, celebrating the abundant, or, the opposite. Climate chaos, economic collapse, civil strife, or a number of other causes, which may be beyond our control, may make our future choices futile and meaningless; moot. Localization, now, is our best, most logical course of action and it is time to ask ourselves which of the options above we want to transition into.
We, in Mendocino County, may not be able to provide all of our wants, but we can certainly see to our needs. Fulfilling wants before needs has gotten us into this mess as much as greed, political incompetence, and ignorance. It is time for a transition and we need to decide which way it will go.
Only a certain amount of fiber can be extracted from the forests without depleting the soils. Until our forests have recovered we need to develop other means of supplying ourselves with fiber from alternative sources. Mendocino County can support the production of fiber in many forms; wool, wood, plant fibers, bamboo, willow, fungi, all grow well in Mendocino County and in Northern California. As the health and productivity of our forests decline and the threat of catastrophic forest fire increases these other fibers will become more valuable and necessary in our area. As work is done in the watersheds that helps the natural healing power of nature rehabilitate the landscape— returning streams to natural functioning capabilities, and, as the larger trees mature, the removal of small diameter poles and understory fuel loads to supply a source of useable building materials, bio-fuels, and fiber— the amount is limited by the need to re-cycle nutrients in the forest soils to maintain fertility. Other sources of fiber will need to be developed, many of which we already know and which have higher fiber content that provides superior structural strength when compared to traditional wood sources.
This post explores the use of several plant sources of fiber and gives some background of their use and properties. Below I list Bamboo, Kenaf, and Hemp. Other forms of fiber, such as wool, straw, fungi and willow are also good sources of fiber and vital to a sustainable future, although I do not include them here to save space. For the Bast plant section below I am quoting sections from the 1996- Bast Fiber Applications for Composites Report, authored by, Erwin H. Lloyd (firstname.lastname@example.org) and David Seber (email@example.com). This 1996 document does not look at Bast fiber in terms of clothing and fabric but for composite (wood and plastic) building materials which are very strong for their weight.
Bast fiber plants, as well as other fiber producing plant species, provide a means to supplement for traditional forest products and even capture new markets through the use of alternative raw materials which possess unique and beneficial properties. Bast plants include flax, kneaf and hemp, and have been used by many civilizations for a period of at least 4000 years. Fibers such as bamboo and hemp are also exceptional for clothing yet I only make short reference to these uses. This “Potential Community Development Plan” is not intended to be complete but to stimulate community dialogue.
From the 1996- Bast Fiber Applications for Composites
“Bast fibers have been grown for centuries throughout the world. Bast plants are characterized by long, strong fiber bundles that comprise the outer portion of the stalk. Bast plants include flax, hemp, kenaf, sunn-hemp, ramie, and jute. The focus of our research has been on the species that can grow in temperate regions of the world, namely flax, hemp, and kenaf. These fibrous plants have long been noted for their exceptional strength in cordage and paper.
The word “bast” refers to the outer portion of the stem of these plants. This stringy, vascular portion comprises 10 – 40% of the mass of the stem depending upon the species of bast plant, as well as the particular variety, or cultivar, within a bast plant.
The remainder of the stem inside this bast layer is a different type of fibrous material, which has different names depending upon the species selected. This inner material is known as shives when referring to flax and sometimes hemp, as hurd in the context of hemp, and as core when from kenaf. For the purpose of simplicity and consistency, we will use the word “core” when discussing this portion of the bast plant.”
Overall Advantages of Bast Plants
“In general, bast plants possess the following benefits:
1. High tensile strength in bast portions, especially in fiber varieties.
2. Bast plants have a relatively low specific gravity of 0.28 – 0.62, yielding an especially high specific strength, i.e. strength to weight ratio, (Kozlowski, Mieleniak, Przepiera, 1994).
3. Generally high fiber productivity rates, rivaling and even surpassing that of the most commercial tree species.
4. Potential for even greater productivity, bast portions, and mechanical properties through focused genetic breeding.” (I hope they mean hybridizing, evb)
Overall Limitations of Bast Plants
“In general, bast plants also have the following limitations:
1. Rotations at least every other year generally required.
2. Limited research for composite applications in North America.
3. Lack of related agricultural infrastructure in North America.
4. Relatively high absorption of moisture in core portion.
5. Diminished board properties when using core for particleboard.
6. Difficulty in handling long fiber bundle lengths for processing.
7. Difficulty in applying binder to long fiber bundle lengths.”
Advantages of Hemp:
“Hemp shows the following strengths:
1. Hemp requires less moisture to grow than kenaf.
2. Hemp’s fiber-bundles are stronger and tougher than those of kenaf, generally comparable to varieties of flax, and most other known fiber species.
3. Hemp is generally pest resistant, drought resistant, and light frost resistant.
4. With proper leaf removal, hemp has low net nutrient requirements and requires minimal cultivation.
5. Hemp provides greater fiber yields in areas generally north of the 40th latitude than most other fiber crops, generally surpassing flax by 10%.”
Disadvantages of Hemp:
“Hemp also has the following weaknesses:
1. Restrictions of its growth and cultivation in North America, especially in the United States.
2. Lower fiber yields than kenaf and other tropical species in the warmer portions of the United States and more southerly regions.
3. Lower bast fiber portions relative to kenaf and flax.
Table 1 compares the chemical composition of these bast plants with that of wood.
Table 1: Comparative Chemical Composition:
FIBROUS MATERIAL: CELLULOSE HEMI- CELLULOSE LIGNIN EXTRACTIVES ASH
FLAX 78.5 9.2 8.5 2.3 1.5
HEMP 68.1 15.1 10.6 3.6 2.5
KENAF (bast) 60.8 20.3 11.0 3.2 4.7
CONIFEROUS 48.0 15.0 25.3 11.5 0.2
DECIDUOUS 52.8 21.8 22.3 2.7 0.4
Source: Danforth International, and TAPPI
Table 5 illustrates the fiber bundle tensile strength properties of the various bast fibers are significantly higher than those of wood species. (Douglas fir, Southern Pine, Aspen vs. Hemp, Kenaf, Flax). In light of this issue, higher structural applications appear the most promising. This value is an excellent measure of the structural performance we can expect in a particular size and configuration of a product.”
Table 5: Comparative Mechanical/Physical Properties of Bast and Wood Materials:
FIBROUS MATERIAL DENSITY (g/cm3) LENGTH (mm) DIAMETER (um) L/D RATIO TENSILE STRENGTHS (psi)
FIBER BUNDLE RANGE AVG RANGE AVG
FLAX 1.51 1.2 10 – 65 32 10 – 25 18 1,778 51,000
KENAF (bast) - 1.2 1.4 – 5 2.6 14 – 23 21 124 58,000
KENAF (core) 0.31 - 0.4 – 1.1 0.6 18 – 37 30 20 -
HEMP 1.48 1.2 7 – 55 25 13 – 30 18 1,087 118,000
S.Y. PINE 0.51 - 2.7 – 4.6 3.7 32 – 43 38 97 11,600
D. FIR 0.48 - 2.7 – 4.6 3.7 32 – 43 38 97 15,600
ASPEN 0.39 - 0.7 – 1.6 1.2 20 – 30 25 48 7,400
Sources: Wood Handbook; Danforth International; W.S.U., WMEL; Columbus, 1996, Institute of Natural Fibers, U.S.D.A., A.R.S.; The BioComposite Center.
“Kenaf, Hibiscus cannabinus, originating from Africa, has traditionally been a source of bast fiber in India, China, The Commonwealth of Independent States, Iran, Nigeria, and Thailand. Kenaf is a newer crop to the United States that shows good potential as a raw material for use in composite products. Presently, around 4,300 acres of kenaf are cultivated in the United States. 2,000 acres are grown in Mississippi, 1,200 acres in Texas, 560 acres in California, with lesser amounts in Louisiana, New Mexico, and Georgia. Traditionally, kenaf has been known as a cordage crop or jute substitute. Research on kenaf first began in the United States in 1957 and has continued sporadically since that time, (White, Higgins, 1964). Newer advances in decortication equipment which seperates the core from the bast fiber combined with fiber shortages has renewed recent interest in kenaf as a fiber source.”
Advantages of Kenaf:
“Kenaf possesses the following benefits:
1. Excellent yields in southern regions. For example, 15 tons/acre were grown at College Station, Texas in research plots, (Berger, 1969). Actual production yields of 7 -9 bone dry tons/acres can be expected in the warmer regions of Texas.
2. Low harvested whole stalk costs in favorable climatic regions such as southern Texas.
3. Genetic strains have been developed which yield 35% or greater bast portions. This is a relatively high proportion.
4. Considerable progress has been made in developing nematode resistance in the Texas growing region. Nematode susceptibility has long been an encumbrance to the viability of kenaf development.
5. Is competitive showing favorable weed control characteristics.
6. Is viewed favorably by the USDA as a prime candidate for alternative fiber development and has consequently received greater research funding.
7. Strong federal political support.”
Limitations of Kenaf:
“Kenaf also has the following limitations:
1. Low productivity in cooler climates. Its growing season can be as short as 90 – 120 days, and consequently it will grow in almost any region of North America if sufficient moisture is available. The yields of kenaf in Rosemount, Minnesota, south of the Twin Cities, yielded only 2.5 tons/acre in a research plot, compared to the 15 ton/acre yield in College Station, Texas, (Le Mahieu, Oplinger, Putnam, 1991; White, Higgins, 1964). Actual production yields are roughly 60-70% of those in test plots, (Blodsoe, 1996; Cook, 1996).
2. High moisture requirements. 600 mm, (23.6 in) of water is preferable during its growing cycle of 120-150 days, (Vannini, Venturi, 1992).” (end quotes)
Bamboo is actually a grass that grows to a harvestable height of 60 feet in about three to five years and can grow as much as two feet per day. It has an extensive root system that continually sends up new shoots and does not require replanting. Bamboo, as the Bast plants mentioned above and other fiber sources, holds the promise of sustainable, cost effective and ecologically responsible alternatives to short sighted management and the clear cutting of our timberland. Bamboo can be spun into yarn, or processed as a fiber. It has a unparalleled micro-structure of pours that absorb human sweat rapidly. If left in it natural state, not roasting it to change the color (caramelizing the starches and sugars), the fiber makes a pleasant green colored fabric that is bio-degradable, cheaper than cotton and wears as well, or better.
Composite products for building materials made from the plants mentioned in this post include, but is not limited to: Low-density insulation boards, Ceiling Tiles, Substrate for lightweight furniture, Components in manufactured housing, Office partitions, Core materials for doors, and particleboard. These plants offer reinforcing fibers to other materials such as concrete, wood, straw, pultrusion products; reinforcements for thermoplastics and insulation; and cordage, especially jute, sisal, and hemp, has historically been strong. Fabrics for clothing, bedding, drapes, upholstery and more can be added into the value items for these fibers. This also does not include food fibers and their benefits to the human body.
There is a great deal of creativity in our area and much we could do to supply our local fiber needs with a fiber processing and manufacturing facility as a foundation of the Eco-Village/Transition Park concept.
A Potential Community Development Plan for the Masonite Site – Part 1→
Eco-Train, Rail and Depot – Part 2→
Ecologically-Oriented Tourism – Part 3→
Rail to Trail – Part 4→
Autonomous Waste Water Treatment System – Part 5→
Community Interpretive Watershed and Visitor’s Center – Part 6→
Food Processing Facility – Part 7→
Small Diameter Pole Processing Mill – Part 8→
Fiber Processing and Re-Manufacture Mill – Part 9→