Plant and animal fibers have provided humans with, among other things, shelter, vessels in which to hold water and cook food, and thread for making fabrics.
Even tho most of the world has abandoned mud and waddle home construction and baskets smeared with clay as water vessels or cooking utensils, plant fibers as a source of weaving still remains current in use.
In prehistoric times humans probably obtained flexible plant fibers simply by pulling off strips of bark or cutting stems and leaves onto thin, weavable ribbons.
Altho these materials can be lashed and interlaced into mats and baskets, they produce only coarse, stiff items.
Major innovation was the discovery that individual fibers could be separated from surrounding cells and used to weave textiles.
Animal skins probably predated woven material, but plant fibers probably predated animal fibers for woven material.
* Sandals, made of complex woven plant fibers, over 8,000
yrs old, have been found at an archaeological site in
* By 5400 years ago, native people of
* Linen was woven 10,000 years ago in
These dates are fairly recent when you consider that the association of the genus Homo with plants and animals dates back hundreds of thousands of years. The recency is understandable when you consider that:
Only a small number of animals (sheep, camels, vicunas, guanacos, goats, rabbits, and the silk moth) and relatively few plants produce fibers that can be twisted or spun.
Humans had to appreciate the nature of fibers, learn which plants contained them, and learn how to extract them before spinning and weaving them.
1. With the exception of synthetic polymers, most economically important products, such as cordage, paper, textiles, are derived from plant fibers.
2. Fibers are elongate cells with tapering ends, and very thick, heavily lignified cell walls.
3. Fiber cells are dead at maturity and function as support tissue in plant stems and roots.
4. The lumen, or cavity inside mature, dead fiber cells, is very small in cross section.
5. Fibers are one of the components of sclerenchyma tissue, along with shorter, thick-walled sclereids (stone cells) which produce the hard tissue of peach pits and the gritty texture in pears.
6. Fibers are also associated with the xylem and phloem tissue of monocot and dicot stems and roots, but generally not the wood of gymnosperms (softwoods).
a. The primary reason why gymnosperm woods are generally softer and lighter than angiosperm woods is the presence in angiosperm wood of dense clusters of heavily-lignified, thick-walled fiber cells.
b. The fiber cells increase the hardness and density of angiosperm wood.
Vegetable fibers Animal fibers
Composed of cellulose
Composed of protein
Not subject to denaturation by high temperatures. Cotton sheets can be boiled when washed.
Heat cracks protein backbone of animal fiber making it brittle. Woolen garments ruined by hot water.
Requires elaborate treatments to ensure successful color adherence
Accepts dye readily
Immune to animal pests but, like paper, attacked by fungi, mold, and termites.
Susceptible to attack by animal pests, such as moths and silverfish.
Less elastic than animal fibers.
More elastic than vegetable fibers.
High affinity for water: more absorbent.
Low affinity for water: not absorbent.
The fundamental chemical difference, between cellulose and protein, determines how the 2 types react to heat, various chemicals, water, and predatory organisms.
With the exception of synthetic polymers, most economically important products, such as paper, cordage (cords and ropes) and textiles, are derived from plant fibers.
Properties of textile fibers
1. Fibers can be spun if they have structural properties that cause individual strands to clasp one another when twisted.
a. Most animal hairs cannot be spun because they are too slippery to stay together when twisted around one another.
2. Elastic properties are a measure of the facility with which a fiber can regain its original shape after it has been stretched.
a. The amount a fiber has been twisted, the way in which the cells are held together, and the number of cells per fiber contribute to its elasticity.
3. Fibers have different densities of weight relative to an equal volume of water, which affects how fibers made from them will drape.
4. Fibers high in cellulose are considered valuable because cellulose is extremely strong with properties of tensile strength rivaling that of steel.
5. Fibers high in lignin are generally of poorer quality, browner in color, with lower mechanical strength.
Kinds of fibers
1. Bast fibers – comes from phloem tissues in the stems of various dicotyledons (linen from the flax plant)
2. Hard fibers – come from the leaves of a few monocotyledonous plants century plant, Manilla hemp).
3. Surface fibers – found on the covering of seeds, leaves, or fruits; cotton cloth is made from seed hairs covering the surface of cotton seeds
Despite the fact that various fibers come from many different and unrelated plants, the same basic procedures are used to separate the fibers from the masses of cells in which they are embedded. The primary processes are: retting, scotching, decorticating, and ginning.
Separating fibers from masses of other cells in which they are embedded.
1. Retting (bacterial rotting).
a. Extraction process that rots away the soft plant parts and leaves fibers intact.
b. Used mainly for bast fibers (phloem tissues of dicots) and takes advantage of the fact that fibers have thicker cell walls than do most other plant cells, and are therefore comparatively resistant to breakdown by bacteria.
c. Plant material can be retted by dumping the mass into tanks of stagnant water, or simply allowing it to remain on the ground where it will be repeatedly covered with dew.
d. During retting, tissues absorb water and swell, causing release of soluble compounds that help provide nourishment for decomposing bacteria.
e. Retting takes a few weeks.
1. The mass of rotting material must occasionally be tested to ascertain the point at which soft tissues, but not fibers, have disintegrated.
f. There may be epidermal and thick-walled woody xylem cells that can persist.
1. These are removed by washing and drying the material after retting.
2. They are then "broken" by means of being forced under fluted rollers.
3. the rollers crumbles the brittle material, but not the more flexible bast or leaf fibers.
4. Broken pieces are then removed from fibers by the process of beating and scraping, called scutching.
5. Finally, fibers are drawn down across a set of vertical pins resembling a comb, called hackling.
Decorticating - entails crushing plant material and scraping nonfibrous material from fibers. Used primarily for leaf fibers.
Ginning - unique to seed fibers. Seeds are pulled free from the fibers covering them.
Once extracted and cleaned, fibers can be further processed by bleaching or heating, or both, in an alkali solution. Fibers are usually bleached before dying so their natural tans and brown pigments don't effect the final color.
Seed and fruit fibers
1. Although seed and fruit fibers come from different parts of the fruit, both aid in seed dispersal, but by different mechanisms.
a. Long fibers on seed surfaces promote dispersal by wind. (e.g. tufts of hair on top of milkweed, Asclepias spp.).
b. Fibers within fruit wall generally protect seed or provide buoyancy for water dispersal, or both (coconut).
2. Few plants have seed or fruit fibers long enough for spinning. Cotton is the notable exception because it produces seed fibers that can be spun into thread.
a. Seed fibers from milkweed and kapok (Ceiba pentandra, Bombacaceae) are too fine and slippery to spin. These are used primarily as stuffing material and kapok was formerly used for life preserves because it’s lightweight and water resistant and has fibers that trap air.
are produced on the inner surface of the seed capsule of the kapok tree, in
tropical regions of the
2. It's an enormous rainforest tree with a massive buttressed trunk.
3. Hairs are coated with a highly water-resistant, waxy cutin.
4. The empty lumen is larger than cotton hairs and hence the fiber is lighter in weight.
5. A kapok-filled life jacket can support 30 times its own weight in sea water.
6. Milkweed hairs were used as a substitute for kapok during WWII.
7. The hairs can also be twisted into dental floss.
b. Coconuts are unique because they produce the only fruits from which fibers (coir) are extracted from the pericarp for commercial use.
1. Bulk of mature coconut consists of thick, fibrous mesocarp that constitutes source of a fiber called coir.
a. Coir fibers are made up of bundles of cells that are longer than cotton fibers but shorter than most bast or leaf fibers.
b. High-grade coir produced by harvesting and husking 10-month old (immature) coconuts.
1. Husks are retted for 8-10 months in brackish water.
2. When soft, husks are thoroughly washed, beaten to remove pulpy remains, shaken, and washed again.
3. Clean fibers are spun into yarns primarily used for ropes and matting.
c. That the most valuable coir fibers come from unripe coconuts presents an economic problem because the most valuable commodity obtained from coconuts is copra, the dried coconut endosperm, which is eaten or used for oil.
1. Copra can be obtained only from mature fruits.
2. Consequently, although mature fruits yield fibers that are tougher than those of young coconuts, most coir is extracted from old husks that remain after the copra has been removed from ripe fruits.
a. Most important fiber today; most important nonfood plant commodity.
b. Large amount of fiber produced by each plant combined with the fact that picking, processing, and manufacturing of textiles from cotton cost less than processing other fibers.
c. Versatile fiber that produces textiles that dye well, and withstands rigorous washing.
d. Each cotton fiber is a single long epidermal seed coat cell. Unicellular hairs that grow out of the surface of the seed after fertilization.
1. Cells are so long they resemble hairs.
2. The hairs are twisted into usable thread which is tough and strong.
3. In cultivated cotton, there is a second layer of short fuzzy hairs underneath the long fibrous hairs. These short hairs, or linters, are removed and used in paper making when cottonseed is used as an oilseed crop.
4. Cotton thread is spun from billions of microscopic hairs covering the surface of cotton seeds, each hair up to 50 mm (2”) long. The total length of hairs in a single cotton boll (one seed capsule) may exceed 300 miles. (How many miles from a standard 500 lb bale?)
Gossypium arboreum and G. herbaceum (
1. Both have short fibers, or staples, and both were
eventually replaced by
2. G. hirsutum and G. barbadense are new World tetraploids.
excavations date to 3,400 BCE in
b. G. hirsutum comprises 95% of the world's supply of cotton.
c. G. hirsutum is relatively resistant to boll weevil.
d. Cotton hairs (lint) of the tetraploid species may be up to 50 mm (2") long.
e. Most species of cotton are tropical perennials, but in cultivated species, humans have selected for an annual habit and the ability to bloom and fruit in temperate lattitudes.
1. Growing cotton as an annual is advantageous for farmers because it ensures a short stature, uniformity of plant size, and synchronous fruiting.
2. On modern farms, plants are often sprayed with a defoliant when cotton is mature so that the foliage will not interfere with harvesting machines that pluck mature bolls from plants.
3. Once picked, seeds with their fibers must be removed from the fruits; fibers are then separated from the seeds.
4. Most Americans know that Eli Whitney invented the cotton gin, a machine that pulls cottonseeds from the fibers, in 1794, but the importance of this equipment may not be widely appreciated.
In 1791, three
years before Whitney’s invention, the
ii. By 1800, exports had jumped to 30, 000 bales.
f. Sizing – consists of the addition of a thick substance, such as starch or a gel, on the surface to stiffen (firm) it and fill surface irregularities. Cotton is usually sized with starch or resin.
1. important for threads that will be used for the warp (major loom threads).
2. sizing material washed out after weaving is done.
3. increase strength of thread
g. Cotton fabrics used to shrink
1. There was the tradition of buying a cotton garment 1 size too large in anticipation of shrinkage due to initial washing.
2. Sanforization (1970) is an ammonia process that swells cotton fiber and prevents their shrinkage after washing.
h. Cotton fabric has a tendency to wrinkle when washed.
1. Permanent press - chemicals are used to cross-link the cellulose polymers of cotton cloth causing the fabric to retain shape it had when chemicals were first applied.
2. This process also keeps surfaces smooth and allows pleated or ruffled garments to retain shape after washing.
Bast fibers from the bark of stems (soft fibers)
1. Thick-walled fiber cells occurring in the phloem parenchyma of stems of various dicots.
2. Bast fibers constitute the main source of stem fibers.
3. Individual bast fibers can be made up of hundreds of cells and can be over 4.6 m (15') long.
4. Fibers usually separated from stems by retting.
Jute (Corchorus capsularis) Tiliaceae - world's foremost bast fiber
1. Jute has been used since prehistoric times.
2. Probably yielded fibers for some of the sackcloth referred to in the Bible.
3. Herbaceous annual, up to 5 m tall; yields fibers 1.8 - 3 m (6-10') long.
4. Fibers are relatively inelastic, and tend to disintegrate rapidly in water.
5. Fibers are separated from the stems by deep-water retting.
6. Their roughness, brittleness of fibers, and inability to hold dyes promote use of jute fibers for coarse goods such as carpet backing, canvas, twine, "gunny sacks", burlap, etc.
7. Popularity of jute is primarily due to its low cost, which results from its raid growth and the ease with which its fibers can be extracted from the stem.
Flax (Linen) Linum usitatissimum. Linaceae.
1. Oldest textile fiber used by humans.
digs uncovered remains of flax species in ancient settlements occupied by
b. Egyptian mummies dated about 5,000 years ago were generally wrapped in linen cloth.
c. Carvings on Egyptian tombs document its cultivation along with wheat, figs, and olives.
2. Etymology - the words 'line' (as in straight lines) and lingerie and the generic name, Linum, are derived from the Latin word for linen.
Flax is native to
4. The plants from which fibers are obtained are tall, little-branched, annuals that yield oil as well as fiber.
5. Flax fibers are smooth, long, straight, and 2-3 times stronger than cotton fibers. They are used for making buttonholes and button thread, as well as for hoses and mailbags.
6. Flax is generally obtained by dew retting the cut stalks of mature plants.
a. This takes about 3 weeks.
b. Plants are now sometimes uprooted and chemically retted (chemicals dissolve the matrix between cells before retting begins).
c. Because of hand labor involved in traditional flax fiber extraction, linen has always been a relatively expensive textile.
7. Linen textiles are generally soft, lustrous, and water-absorbent, and linen is also used for towels.
8. Linum is also the source of linseed oil, an unsaturated drying oil used in the original linoleum and in the paint industry. Linoleum = linum (flax) + oleum (oil).
Hemp (Cannabis sativa) Cannabaceae.
1. Cannabis initially spread around the world because of its fiber, not because of its resinous compounds (THC).
Native to western
consumed along with millet, rice, barley, and soybeans in ancient
3. Dioecious, annual herbs.
4. Hemp fibers are the longest of any bast species, ranging from 1.5 - 4.5" (5-15') in length.
a. Staminate plants produce the best and longest fibers, up to 2 meters long.
b. They were used to weave the cloth of which most Chinese garments were made in ancient times.
c. The yarn woven from these fibers were exceedingly fine, so much so that people were buried in hemp garments.
5. Hemp produces dark, rough fiber and as a result is typically used for cordage, rope, canvas (the word derives from Cannabis), covered wagons, and sailcloth.
6. Etymology: Levi Strauss originally made work clothes of hemp;
it was imported from Mines,
7. Altho cultivation of hemp has been illegal in the
8. Hemp was once extensively planted throughout the
9. Grass root movement to legalize the production of industrial hemp. Supporters for legalization point out the low THC content in the hemp plant.
10. Requires no irrigation or pesticide use: cotton requires considerable amounts of both.
11. Navajo Nation now considering hemp production on their lands.
12. The Chinese harvest many tons of hemp fiber annually to produce fiber for paper, rope, and cloth.
plant, Apocynum cannabinum, (Indian
hemp), was an important fiber plant of native North American people, and is native
to certain areas in
Leaf Fibers (Hard fibers)
1. Most leaf fibers are obtained from rapidly growing monocots with fibers that can be easily and inexpensively extracted by decorticating machines.
2. The fibrous strands occur within the phloem in the vascular bundles scattered in leaves and leaf bases.
3. Within the leaves, the thick-walled fiber cells provide support.
4. Once extracted, the fibers can be spun, but they are too stiff to be made into textiles suitable for modern clothing.
5. The name 'hard' refers to its stiffness.
6. Hard fibers tend to be shorter than bast fibers.
7. Leaf fibers, however, make better ropes than do bast fibers.
8. Although other plants are generally used, two genera, Agave and Musa, supply virtually all the commercially important leaf fibers.
Sisal comes from
the leaves of Agave sisalana, native
2. In addition to fibers, A. sislana has sharp spines on the ends of its leaves that have been used by native peoples as needles.
3. Combination of fiber and sewing utensil gave rise to the common name, "needle and thread plant".
4. Today the fibers are used for sacking, mats, and tea bags and as reinforcements for materials such as rubber.
5. The sap tapped from this agave can also be fermented into a mildly alcoholic wine known as pulque.
6. Fiber removal
a. Outer mature leaves are cut at the base, carted to factory, and fed between rollers that squeeze out most of the water and turn the soft tissues into an amorphous mush that is scraped away from the fibers.
b. Fibers are then washed and hung in the sun to dry.
7. The sun-dried leaves of Yucca elata are used extensively for the main visible white coils in baskets of native North American people, including the Papago, Pima, and Havasupai.
B. Abaca (Manila hemp)
Manila hemp comes
from Musa textilis (Musaceae), a
relative of the banana, native to the
2. Fibers are extracted from the outer parts of the leaf bases that make up the "stem" of these giant herbaceous plants.
Most people have
come into contact with products using Manila hemp in the form of tea bags,
dollar bills, "
4. They make the finest ropes, which have held ships to docks throughout the world. Manila hemp rope is being replaced with nylon in many parts of the world.