Blissful

Hemp

Hemp: A New Crop 

By

Ernest Small and David Marcus

*This paper was considerably improved by criticism provided by A. McElroy.

“Hemp” refers primarily to Cannabis sativa L. (Cannabaceae), although the term has been applied to dozens of species representing at least 22 genera, often prominent fiber crops. For examples, Manila hemp (abaca) is Musa textilis Née, sisal hemp is Agave sisalina Perrine, and sunn hemp is Crotolaria juncea L. Especially confusing is the phrase “Indian hemp,” which has been used both for narcotic Asian land races of C. sativa (so-called C. indica Lamarck of India) and Apocynum cannabinum L., which was used by North American Indians as a fiber plant. Cannabis sativa is a multi-purpose plant that has been domesticated for bast (phloem) fiber in the stem, a multi-purpose fixed oil in the “seeds” (achenes), and an intoxicating resin secreted by epidermal glands. The common names hemp and marijuana (much less frequently spelled marihuana) have been applied loosely to all three forms, although historically hemp has been used primarily for the fiber cultigen and its fiber preparations, and marijuana for the drug cultigen and its drug preparations. The current hemp industry is making great efforts to point out that “hemp is not marijuana.” Italicized, Cannabis refers to the biological name of the plant (only one species of this genus is commonly recognized, C. sativa L.). Non-italicized, “cannabis” is a generic abstraction, widely used as a noun and adjective, and commonly (often loosely) used both for cannabis plants and/or any or all of the intoxicant preparations made from them.

Probably indigenous to temperate Asia, C. sativa is the most widely cited example of a “camp follower.” It was pre-adapted to thrive in the manured soils around man’s early settlements, which quickly led to its domestication (Schultes 1970). Hemp was harvested by the Chinese 8500 years ago (Schultes and Hofmann 1980). For most of its history, C. sativa was most valued as a fiber source, considerably less so as an intoxicant, and only to a limited extent as an oilseed crop. Hemp is one of the oldest sources of textile fiber, with extant remains of hempen cloth trailing back 6 millennia. Hemp grown for fiber was introduced to western Asia and Egypt, and subsequently to Europe somewhere between 1000 and 2000 BCE. Cultivation in Europe became widespread after 500 ce. The crop was first brought to South America in 1545, in Chile, and to North America in Port Royal, Acadia in 1606. The hemp industry flourished in Kentucky, Missouri, and Illinois between 1840 and 1860 because of the strong demand for sailcloth and cordage (Ehrensing 1998). From the end of the Civil War until 1912, virtually all hemp in the US was produced in Kentucky. During World War I, some hemp cultivation occurred in several states, including Kentucky, Wisconsin, California, North Dakota, South Dakota, Minnesota, Indiana, Illinois, Ohio, Michigan, Kansas, and Iowa (Ehrensing 1998). The second world war led to a brief revival of hemp cultivation in the Midwest, as well as in Canada, because the war cut off supplies of fiber (substantial renewed cultivation also occurred in Germany for the same reason). Until the beginning of the 19th century, hemp was the leading cordage fiber. Until the middle of the 19th century, hemp rivaled flax as the chief textile fiber of vegetable origin, and indeed was described as “the king of fiber-bearing plants,—the standard by which all other fibers are measured” (Boyce 1900). Nevertheless, the Marihuana Tax Act applied in 1938 essentially ended hemp production in the United States, although a small hemp fiber industry continued in Wisconsin until 1958. Similarly in 1938 the cultivation of Cannabis became illegal in Canada under the Opium and Narcotics Act.

Hemp, grown under license mostly in Canada, is the most publicized “new” crop in North America. Until very recently the prohibition against drug forms of the plant prevented consideration of cultivation of fiber and oilseed cultivars in Canada. However, in the last 10 years three key developments occurred: (1) much-publicized recent advances in the legal cultivation of hemp in western Europe, especially for new value-added products; (2) enterprising farmers and farm groups became convinced of the agricultural potential of hemp in Canada, and obtained permits to conduct experimental cultivation; and (3) lobby groups convinced the government of Canada that narcotic forms of the hemp plant are distinct and distinguishable from fiber and oilseed forms. In March 1998, new regulations (under the Controlled Drugs and Substances Act) were provided to allow the commercial development of a hemp industry in Canada, and since then more than a thousand licenses have been issued. Hectares licensed for cultivation for 1998–2001 were respectively, 2,500, 14,200, 5,487, and 1,355, the decreasing trend due to a glut of seed produced in 1999 and pessimism over new potential regulations barring exports to the US. Information on the commercial potential of hemp in Canada is in Blade (1998), Marcus (1998), and Pinfold Consulting (1998). In the US, a substantial trade in hemp products has developed, based on imports of hemp fiber, grain, and oil. The American agricultural community has observed this, and has had success at the state level in persuading legislators of the advisability of experimental hemp cultivation as a means of evaluating the wisdom of re-establishing American hemp production. However, because of opposition by the federal government, to date there has only been a small experimental plot in Hawaii. Information on the commercial potential of hemp in the US is presented in the following.

Cannabis sativa is extremely unusual in the diversity of products for which it is or can be cultivated. Popular Mechanics magazine (1938) touted hemp as “the new billion dollar crop,” stating that it “can be used to produce more than 25,000 products, ranging from dynamite to Cellophane.” Table 1 presents the principal products for which the species is cultivated in Europe, all of which happen to be based on fiber. This presentation stresses the products that hold the most promise for North America, which also include a considerable range of oilseed applications (Table 2; Fig. 1).

Table 1. Hemp fiber usage in the European Union in 1999 (after Karus et al. 2000).

Table 2. Analysis of commercial Cannabis product potential in North America in order of decreasing value toward the right and toward the bottom.

hail hemp!!!!

fiber fiber fiber fiber http://www.hort.purdue.edu/newcrop/ncnu02/v5-284.html

how strong it is.....

Henry Ford swinging an axe at his 1941 car to demonstrate the toughness of the plastic trunk door made of soybean and hemp. (From the collections of Henry Ford Museum & Greenfield Village.)

 Hemp-based erosion control blanket. Top left: Close-up of 100% hemp fiber blanket. Top right: Grass growing through blanket. Bottom: Demonstration of installation of blanket, near La Rivière, Manitoba. (Courtesy of Mark Myrowich, ErosionControlBlanket.com)

Most insects cause only limited damage to hemp, and substantial insect damage is uncommon, so the use of insecticides is very rarely required.

 Coconuts for Carssssssssssssssssssssssss!!!!

Researchers in Texas are making car parts out of coconuts.

A team at Baylor University there has made trunk liners, floorboards and car-door interior covers using fibers from the outer husks of coconuts, replacing the synthetic polyester fibers typically used in composite materials.

The approach has potential because coconuts are an abundant, renewable resource in all countries near the equator, including the Philippines, Indonesia and India. The husks are burned or thrown away, generating garbage. This is the first time that coconut fibers have been used to make these automotive products, said Walter Bradley, an engineering professor who is leading the project.

In Ghana, as one of Bradley's students told him, the discarded husks pile up in mounds, creating a health hazard because they collect water where malaria-causing mosquitoes can breed.

"We are trying to turn trash into cash to help poor coconut farmers," Bradley said, adding that the long-term goal is to increase demand for coconuts to millions of pounds, and thereby raise their market price.

Currently, there are about 11 million coconut farmers in the world making an average annual income of $500, he said.

Husks, not shells

The production process starts with the coconut husk.

"The coconut that you see in the grocery store has a real hard shell that comes in a larger volume that's twice as big — the husk, that is very fibrous," Bradley told LiveScience.

Coconuts now are used primarily to produce coconut milk or coconut oil (which is the milk minus the water in it).

The husk is made mainly of fiber and coconut dust, or pith. The pith is spongy at first, but dries and contracts into dirt-like particles that Bradley's team confirmed to have the capacity to absorb 10 times its weight in water.

"The fiber has very good strength, stiffness and ductility, and potentially can be used for all kinds of things," Bradley said, including a more environmentally friendly particle board (used in construction) that requires no binders.

A lightweight composite

The husk fibers are blended with polypropylene fibers before being hot-pressed (compression-molded) into required shapes. The coconut fiber provides a rigid architecture for the lightweight, yet stiff, composite.

Preliminary testing shows that the coconut composites can meet the specifications for industrial tests, Bradley said. In fact, the mechanical properties of coconut fibers are just as good, if not better, than synthetic and polyester fibers when used in automotive parts, he said. Also, coconuts also do not burn very well or give off toxic fumes, which is key in passing tests required for their use in commercial automotive parts.

Bradley's team is now working with a Texas-based fiber processing company that supplies unwoven fiber mats to four major automotive companies. The team is creating a 600-pound roll of the composite material and assisting with the safety performance tests for certification.