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By David P. West, Ph.D*.

Author's note: This essay is a condensation of Fiber Wars with greater emphasis on practical farming. It was never finished and languished as a draft to the present. Some images are still missing. As opportunity allows, it will be given further attention.

Part 1


1. Antebellum

Our concern here is with hemp.

When we use the word "hemp" we do so to distinguish it from other varieties1 of Cannabis sativa L. that are horticultural, not agronomic crops and that have other uses but are generally unsuitable for the manufacture of durable goods such as paper, textiles or fiberboard. Of those other varieties, we will have little to say in this context, except in presenting evidence to verify the distinction of types.

The first historical record of utilization of the hemp plant for its stem fiber comes from the Chinese who described the plant they called ma as having been introduced by the Emperor Shen Nung in the 28th century BCE. The bulk of opinion locates the original wild Cannabis ancestor growing in a general area between western China and the eastern Caucasus, north of the Hindu Kush. This wild ancestor is not found today.

"Run away, the 23rd inst. a negro fellow, named Jack, 26 years of age, straight well made fellow, has on an old black wool hat, coarse hemp linen shirt...."2

Jute, ramie, abaca, sisal, kenaf and cotton are fiber crops adapted to lower latitudes. Before cotton took over, hemp and flax (in spite of the latter's origin in Africa) were the principal crops used for fabric and cordage by temperate cultures. The fineness and quality characteristics of these two fibers overlap and depend on the growing conditions, seed variety and post-harvest handling. Flax, with lower lignin content in the fiber, was for centuries the premier fiber for high class apparel in western cultures. There are exceptions to this general trend, however. In Hungary, for instance, the traditional national costume was made of hemp cloth. In Japan, hemp was—and is–the fabric of royalty. (The subject of hemp in Japan is so vast as to require consideration all its own.) Whereas in antebellum America, hemp homespun—called "Kentucky jeans"–was commonly used to clothe the slave population.

Hemp's major use was as a cordage fiber. Its natural resistance to rot recommended it for maritime uses, and, as European seafaring expanded, so did the importance of hemp. So critical was hemp to naval powers that laws were passed in England and in the American colonies requiring farmers to allot a portion of their acreage to the production of hemp. Were it not for hemp, European expansion, the Age of Exploration and the discovery of the New World would certainly not have occurred as they did. Sailing ships carried hempseed in their stores and the crop was seeded in new lands to provide for the repair of marlines, hausers and sails. Ships were caulked with oakum made of the short hemp "tow" fibers.

Hemp was growing in Chile by 1545, in New England by 1629. The Founding Fathers were strong promoters of hemp. For a time following the War of Independence, farmers could pay their taxes in hemp. Oft cited, George Washington admonished (caveat), "Sow it everywhere."3 Thomas Jefferson, a strong proponent of hemp as a crop, invented a hemp brake and experimented with different genetic varieties.

Hemp production during the Revolutionary period was greatest in Virginia where its labor requirement led to a rapid increase in that state's slave population.4 Hemp fabric clothed the slaves, but was too coarse for the gentle classes.

Hemp moved west with the Pioneers. It was first planted in Kentucky on Clarke's Creek near Danville by Archibald McNeil in 1775. The growth and vicissitudes of the Kentucky hemp industry have been described in detail by James Hopkins in his History of the Hemp Industry in Kentucky.5 Kentucky was the principal producer of hemp fiber until the Civil War.

The mainstay of the Kentucky industry was baling rope and bagging used for cotton bales. Hemp accounted for 5% of the weight of a cotton bale and the fortunes of the Kentucky industry rose and fell with the cotton market. But despite substantial efforts on the part of the government and private individuals to encourage the use of Kentucky hemp by the US Navy, it was generally rejected for quality in favor of imported Russian "Riga Rein" hemp. After the Civil War, jute and iron bands replaced hemp for cotton bales and the Kentucky industry declined.

"The Federal Government in 1841 authorized a bounty, which allowed for the payment of not more than $280 per ton for American water-retted hemp, provided it was suitable for naval cordage. Many of the planters prepared large pools and water-retted the hemp they produced. But the work was so hard on Negroes that the practice was abandoned. Many Negroes died of pneumonia contracted from working in the hemp pools in the winter, and the mortality became so great among hemp hands that the increase in value of the hemp did not equal the loss in Negroes."6"

Hemp fabric can be fine, strong and very durable. But great skill is required to produce quality fiber with retting preferably done in water rather than on the ground. This art was practiced in Europe, particularly in Italy, which was credited with having hemp fabric of the finest quality. The US Navy insisted on water-retted hemp. In an effort to promote the domestic industry, the government offered inducements for water-retting. In the final analysis, these efforts failed.

Another obstacle to the industry was the location of cordage manufacturing on the coast. Rope walks were established in Kentucky as early as 1814, but the major manufacturing center was Boston, near the shipyards. Raw fiber could reach the east coast by ship from the East Indies as cheaply as from the western frontier, so hemp had to compete with tropical cordage fibers. For a time, tariffs protected the domestic bast fiber industry.

During the nineteenth century, Russia supplied most of the hemp fiber used internationally for naval cordage. (We are told that Napolean's reason for invading Russia was to cut off England's access to Russian hemp upon which the Royal Navy's power depended.) The USS Constitution had over sixty tons of hemp in its sails and riggings.

From the sixteenth through the ninteenth century, the supply of hemp fiber was a matter of significant military concern. The strategic importance of hemp would be revisited again in 1941 when Japan's invasion of the Philippines severed US access to Manila hemp (abacá) leading to a brief resurrection of the domestic hemp industry. Hemp is still listed among agricultural products considered strategic necessities by the US government.7


2. Civil War to Depression

The ages of hemp can be broadly divided at the American Civil War. The classical period, described above, with hemp unchallenged in its maritime use, began to give way in the mid-nineteenth century as abacá, a relative of the banana, preempted hemp for naval cordage. Abaca had several things going for it: it floated on water and did not require tarring; and it could be produced with cheap labor on plantations in the East Indies.

Domestically produced hemp had difficulty competing with abacá and other tropical fibers because of the high labor requirement. It had to be cut by hand and gathered into shocks to dry before being spread on the field for retting. When retting was complete, the stems were gathered up and broken using a hemp brake. Then it was hackled by flaying it on a pin-cushion of long needles to further separate the fiber from the inner woody core of the plant, called "hurds." Prior to the Civil War, this work was done by slaves in the major hemp producing areas of Kentucky and Missouri. After the war, the black population in Kentucky continued to find employment in the winter months breaking hemp.8 The ready availability of this labor force, and its dependence on hemp processing for subsistence, was given as one reason Kentucky's transition to mechanization in the early twentieth century was delayed.

"The practice of weaving flax and hemp upon the old looms experienced a revival and factories began making fibers into cloth. From Fayette County in 1863 came a statement that high prices were being offered for hemp and a hopeful opinion was expressed that "a vast source of profit will be derived by our farmers who will cultivate this crop, as from the present scarcity of cotton, it will doubtless be used to a large extent for clothing as well as for the many purposes for which it has entered into competition as one of the great staples of our country."9

The Civil War disrupted Kentucky's hemp economy because the primary consumer of hemp fiber was the Southern cotton industry. During the war, a federal commission was directed to identify cotton substitutes: it focused on flax and hemp as alternatives.

With the end of the war, cotton agriculture revived and the optimistic prospects for hemp fabric went unfulfilled. Cheap imported fibers, particularly jute-a weaker fiber with no resistance to rot, but suitable for common twine and cotton bagging- increasingly cut into hemp's markets. In 1872, the repeal of a tariff which had protected the domestic bast fiber industry, opened doors to unlimited importation of jute and other tropical fibers. Iron bands replaced vegetable cordage for binding cotton bales. The Kentucky hemp industry never recovered its antebellum dimensions. With the coming of steam-powered ships in the last half of the nineteenth century, hemp acreages declined internationally. The changes brought by abaca and steam relegated hemp to a minor naval function: binding the ends of ropes and caulking. Wire cables, required by law on inland vessels, further reduced the demand for hemp. Under pressure from frontier legislators, the federal government enacted programs to encourage the hemp industry, including the construction of a navy yard in Memphis, Tennessee. Despite these efforts and several failed attempts to expand water- retting, the Kentucky industry continued to decline. Gradually farmers in Kentucky shifted to more dependably profitable crops, principally tobacco. Hemp moved west with the Pioneers: Missouri (1835); Minnesota (1860); Illinois (1875); Nebraska(1887); Wisconsin (1908); California (1912). By 1860, Missouri had replaced Kentucky as the major supplier of hemp. At the same time, hemp was moving north, being first grown in Minnesota that same year. In 1890, the cabinet office of Secretary of Agriculture was created. Its first appointee was Jeremiah Rusk, a former governor of Wisconsin. One of Rusk's first actions was the inauguration of the USDA's Office of Fiber Investigations to encourage domestic bast fiber production. Its first director, Charles Dodge, opined: "There is no reason why hemp culture should not extend over a dozen States and the product used in manufactures which now employ thousands of tons of imported fibers."10 Much of this importation was due to the invention, circa 1880, of the self-binding grain harvester which needed binder twine.

The twine binder brought about the final evolution of the harvesting machine. John F. Appleby, Jacob Behel and Marquis L. Gorham were the pioneers in developing the twine binder and knotter. Imported Manila jute and sisal were woven into balls of binder twine and sold to every farmer who owned a binder. The twine binder, called a "self-binder," more than any other single machine enabled the farmers to expand their wheat crops. In 1882, the McCormick Company, having turned from wire binders to twine binders, sold over fifteen thousand twine binders. The twine binders with their automatic knotters made possible the rapid extension of the wheat belt into the West and Northwest; and large scale farming became common practice in those areas. Schager cites one farm near Casselton, North Dakota, on which sixty self- binders were employed as early as 1882.11

Hemp's greater strength per unit weight made it ideal for this purpose. Writing to Charles Dodge in 1890, one binder manufacturer testified:

There is no fiber in the world better suited to this use than American hemp. It is our judgment, based on nearly ten years' experience with large quantities of binder twine each year, that the entire supply of this twine should be made from American hemp....There are 50,000 tons of this binding twine used annually, every pound of which could and should be made from this home product.12

Mechanization has been a feature of American agriculture from the time of Eli Whitney. It was the key to the agricultural conquest of the nation's breadbasket, the Great Plains. Mechanization progressed rapidly in the northern and western states' wheat and corn growing regions where there developed a tradition of the small local farm implement manufacturers, like the McCormicks and John Deere, with inventive notions. The resurrection of the domestic bast fiber industry required mechanization of the various stages of fiber processing: harvesting (cutting and retting), breaking, scutching, hackling. Lacking mechanization, there was no possibility of hemp competing with the cheap tropical fibers.

"In Nebraska, where the [hemp] industry is being established, a new and important step has been taken in cutting the crop with an ordinary mowing machine. A simple attachment which bends the stalks over in the direction in which the machine is going facilitates the cutting...The cost of cutting hemp in this manner is 50 cents per acre, as compared with $3 to $4 per acre, the rates paid for cutting by hand in Kentucky."13

A machine invented in Nebraska could cut five to seven acres per day compared to half an acre cut by hand using the traditional Kentucky practice. But it was not in the traditional hemp growing regions of Kentucky and Missouri that the new technologies were aggressively applied. Kentucky would remain the source of seed, but the fiber crop moved north.

With the promotion from the USDA's Office of Fiber Investigations, hemp was first planted at three sites in Wisconsin in 1908.14 It did well. Hemp caught the interest of local farmers near Waupon, on the eastern side of the state, who noticed that it cleaned the fields of quackgrass. The success of the hemp experiments in Wisconsin led to the appointment of Dr. Andrew Wright, of the University of Wisconsin Agricultural Experiment Station, as industry steward.

Andrew Wright recognized the necessity of, one, mechanization and, two, locating mills with railway access. Fortunately, by the early twentieth century, Wisconsin was crisscrossed with rail lines. The industry established itself on rail spurs in the east-central part of the state, near Lake Winnebago. With the new mechanical processing and rail spurs coming directly into the mills, the Wisconsin hemp industry prospered and grew. On October 17, 1917, the Wisconsin Hemp Order was inaugurated at Ripon "to promote the general welfare of the hemp industry in the state."15

When the work with hemp was begun in Wisconsin, there were no satisfactory machines for harvesting, spreading, binding, or breaking. All of these processes were performed by hand. Due to such methods, the hemp industry in the United States had all but disappeared. As it was realized from the very beginning of the work in Wisconsin that no permanent progress could be made so long as it was necessary to depend upon hand labor, immediate attention was given to solving the problem of power machinery. Nearly every kind of hemp machine was studied and tested. The obstacles were great, but through the cooperation of experienced hemp men and one large harvesting machinery company, this problem has been nearly solved. The hemp crop can now be handled entirely by machinery.16

Andrew Wright was working with Lyster Dewey of the USDA's Office of Fiber Investigations. Dewey is unarguably the most significant individual in US hemp history. He joined the Office of Fiber Investigations just before the turn of the century and set about evaluating hemp germplasm collected from around the world. His monographs on hemp, published in the USDA Yearbooks of Agriculture, 1901 and 1913,17 remain the most informative writings on hemp in America.

In the 1901 piece, Dewey describes the status of hemp germplasm at that time in the US:

Until comparatively recent times hemp seed of European origin was used in Kentucky, and its effects are still plainly seen in the mixed character of plants too often found in the hemp fields. These plants are so prolific in seed that the growers hesitate to throw them out when harvesting their hemp seed. An ideal hemp plant should be 10 to 12 feet in height, one-fourth to three-eighths inch in diameter near the base, with internodes 10 inches or more in length, and stems prominently fluted, with comparatively large hollows, making them thin-shelled and more easily broken. The fiber is generally tougher on the thin-shelled stalks. The Chinese and best Japanese varieties approach most nearly this ideal. Starting with these as a foundation and practicing a rigid seed selection for a half dozen generations or longer would undoubtedly result in improved varieties of uniform plants adapted to cultivation in this country.18

Dewey explained that beginning in the mid-nineteenth century a shift toward Chinese varieties had taken place. Seed was obtained through the agency of American missionaries in China and was grown for a few generations to increase the seed supply before being planted for fiber.19

Foreign hemp strains required a period of natural selection to adjust to the new North American growing environment. Chinese hemp appeared better suited to North America than European varieties. In a later writing, Dewey remarked that introduced foreign strains had to be grown "for at least three generations (three successive years) in the country where it is to be grown for fiber"20 to achieve satisfactory adaptation to the local growing environment. Out of the Chinese introductions a unique hemp variety was developed which came to be known as "Kentucky hemp." It conformed to Dewey's ideal type and the hollowness of the stem was particularly noted. All hemp has hollow stem (Fig 1), but that of Kentucky hemp was apparently superior since specific attention is drawn to it.21

Figure 1. Contrast in stem hollowness, non-fiber vs. fiber variety (right). From Small, 1979.

We should also take special note of Dewey's remark about the "mixed character" of plants in the fields. This tells us that Kentucky hemp may have originated as a "fusion variety" from the mixing of two previously isolated genetic pools, the Asian and the European. The heterosis released by hybridity would produce more vigorous and fecund plants which "farmers hesitate to throw out." Some modern Hungarian hemp varieties exploit the potential from this same interracial cross.22

If this is the case, then Kentucky hemp was an evolutionary leap comparable to that which corn (maize) was undergoing in this same period from the mixing of previously isolated southern dent and northern flint Zea mays populations. If this fusion occurred-something modern tools for genetic analysis could determine-then American Kentucky hemp was truly a unique and superior type of hemp.


Dewey began actively breeding hemp in 1912. By 1917, the program was producing notably improved stocks. Progress was steady.

1917: "The crop of hempseed last fall, estimated at about 45,000 bushels, is the largest produced in the United States since 1859. A very large proportion of it was from improved strains developed by this bureau in the hempseed selection plats at Arlington and Yarrow Farms."23
1918: "Early maturing varieties, chiefly of Italian origin, are being grown at Madison, Wisconsin, in cooperation with the Wisconsin Agricultural Experiment Station. This is the third year of selection for some varieties, and the results give promise of the successful production in that State of seed of hemp fully equal to the Ferrara of northern Italy."24
1919: "The second-generation hybrid Ferramington, combining the height and long internodes of Kymington with the earliness and heavy seed yield of Ferrara, gives promise of a good fiber type of hemp that may ripen seed as far north as Wisconsin."25
1920: "The work of breeding improved strains of hemp is being continued at Arlington Farm, Va., and all previous records were broken in the selection plats of 1919. The three best strains, Kymington, Chington and Tochimington, averaged, respectively, 14 feet 11 inches, 15 feet 5 inches, and 15 feet 9 inches, while the tallest individual plant was 19 feet. The improvement by selection is shown not alone in increased height but also in longer internodes, yielding fiber of better quality and increased quantity."26

Recently discovered correspondence between Lyster Dewey and the Woodford-Spears Seed Company of Paris, Kentucky, indicates that the improved seed from the USDA breeding program was entering the commercial stream. But despite the earliness of varieties like Ferramington and Kymington, no hempseed industry ever developed in the north. Kentucky continued to supply seed for the Wisconsin industry.

The geographic scale of the US solved a problem which the small nations of Europe could not: the dioecious flowering character of the hemp plant. Because male plants flower first, they are more mature and more lignified when the female plants are ready for harvest. Ideally, for fiber, plants are harvested before they flower. In some primitive systems, the males were removed by hand as soon as they could be recognized and before lignification. Flowering in hemp is controlled by length of the night. If the daylength is long, flowering is delayed. In the US, by growing Kentucky seed in Wisconsin, flowering was avoided and the sexual dimorphism of hemp was circumvented. In China, hemp is harvested at this stage. Maximum fiber yields are obtained if the plants remain in the vegetative state throughout the growing season, hence the area of hempseed production is best located south of the optimum area for fiber production.27 This was the symbiosis which evolved between the seed producers in Kentucky-like Woodford-Spears in Paris, and B.F. Brent in Versailles-and companies like the Rock River Mills and Rens Hemp Company of Wisconsin.

In the Twenties, hemp mills were operating on both the east and west sides of Wisconsin. Wright was able to boast that Wisconsin had more hemp mills than all other states combined.

Dewey's program continued to produce new varieties through the Twenties. In the 1927 USDA Yearbook, he described the breeding technique used to develop the varieties Kymington (Kentucky by Minnesota 8); Chington (from a plant introduction from Hankow, China, able to attain heights of 20 feet); Ferramington (Chinese by northern Italian) and Arlington (Kymington by Chington). Seed of these varieties was supplied to hempseed producers. By 1929, a variety named "Chinamington" was breaking all records for fiber yields. Dewey reported:

"In 1929 three selected varieties of hemp-Michigan Early, Chinamington and Simple Leaf-were grown in comparison with unselected common Kentucky seed near Juneau, Wis. Each of the varieties had been developed by 10 years or more of selection from the progeny of individual plants. The yields of fiber per acre were as follows: Simple Leaf, 360 pounds; Michigan Early, 694 pounds; Chinamington, 1054 pounds; common Kentucky, 680 pounds."28

Despite this progress, by 1930, as the nation struggled under Depression, hemp acreage was again in decline. The uses to which hemp was being put were enumerated by Dewey in a 1931 article titled "Hemp fiber losing ground, despite its valuable qualities:"

"Wrapping twines for heavy packages; mattress twine for sewing mattresses; spring twines for tying springs in overstuffed furniture and in box springs; sacking twine for sewing sacks containing sugar, wool peanuts, stock fed, or fertilizer; baling twine, similar to sacking twine, for sewing burlap covering on bales and packages; broom twine for sewing brooms; sewing twine for sewing cheesecloth for shade grown tobacco; hop twine for holding up hop vines in hop yards; ham strings for hanging up hams; tag twines for shipping twines; meter cord for tying diapharams in gas meters; blocking cord used in blocking men's hats; webbing yarns which are woven into strong webbing; belting yarns to be woven into belts; marlines for binding the ends of ropes, cables and hawsers to keep them from fraying; hemp packing or coarse yarn used in packing valve pumps; plumber's oakum, usually tarred, for packing the joints of pipes; marine oakum, also tarred for calking the seams of ships and other water craft."29

It was largely variations on the same theme: twine.

Fibers are fungible commodities. They move in international markets and are purchased in huge volumes where small price fluctuations are highly significant. In rough times, quality loses to price. Hemp lost to sisal and jute, as natural fibers in general lost out to the new, exciting synthetics.

3. The Thirties

As has been the general trend with agricultural products, many of hemp's markets were being displaced by synthetic materials from the growing organic chemical industry. What was lacking was a determined effort to develop new uses and new markets for hemp. Why was this?

The interplay of political and economic forces in the increasing political power of the South and cotton over agricultural policy, and its effect on allocations for fiber research at the USDA, has been described elsewhere.30 Hemp was not alone in the erosion of its markets. The production of flax for fiber had virtually disappeared. Flax was grown primarily as an oilseed crop. It commanded greater influence than hemp due to the importance of linseed oil for paints and varnishes and linoleum.31 By 1930, the country had less than 1500 acres of hemp, principally in Wisconsin.

In 1933, with the country deep in Depression, the USDA was undergoing radical changes including the first subsidy payments to farmers to limit production of surplus crops. The South depended on cotton.32 So it was that the Office of Fiber Investigations was restructured as the USDA Division of Cotton and Other Fibers and Lyster Dewey's breeding program was terminated. He retired two years later. His last report summarized the success of the program:

The hemp breeding work, carried on by the Bureau for more than 20 years, was discontinued in 1933, but practical results are still evident in commercial fields. A hemp grower in Kentucky reported a yield of 1750 pounds per acre of clean, dew-retted fiber from 100 acres of the pedigreed variety Chinamington grown in 1934. This is more than twice the average yield obtained from ordinary unselected hemp seed.33

How unfortunate that all this germplasm has been lost! We have the National Seed Storage Laboratory in Fort Collins, Colorado, and several regional laboratories charged with the preservation of valuable crop varieties. But in the phytopogrom which subsequently developed, Cannabis would be shunned and with the pariah status and the governmental redtape, Kentucky hemp and Dewey's selected varieties would be lost. As an agricultural variety, Kentucky hemp is effectively extinct. Its feral remnant today we call "ditchweed." It is a repository of important genes, not a threat to society. The extermination campaign being waged against this genetic resource is no less than a crime, a crime against humanity and future generations.

4. Hemp Becomes a Drug Plant

It's probably accurate to say the history of hemp has been, to this point, fairly banal. It was a useful fiber supplanted by technological change. By 1930, it had become an insignificant crop on the verge of being relegated to history's trashcan. During the 1930s, there averaged fewer than 1500 acres of hemp in Wisconsin, with seed production continuing in Kentucky. Yet here we are today with hemp apparently elevated to the status of a plant which can "save the planet." How is it that this minor crop has refused to go quietly into that good night?

Although marijuana (or marihuana, as they wrote in the '30s) would seem to have been the downfall of hemp, it has probably also been the only reason Cannabis did not disappear from human interest. In countries where hemp was not subject to the legal encumberances imposed in the West, hemp acreage also declined percipitously after WWII. Cotton, followed by wool and silk, dominated natural fiber textiles, which lost out on the whole to synthetics. Hemp's association with marijuana did not help, but neither was it the sole cause of hemp's attrition. It is, however, clearly the boot which holds it down. The identification of fiber cannabis with herbal cannabis is as inappropriate as the identification of sweetcorn with fieldcorn. This latter example of plant variety causes little difficulty for most people, who would soon inform their grocer were a substitution attempted.

The identification was forced from the start and continues to be so today. Since our focus here is on hemp as a crop, revelations regarding the motivations which were operative in 1937 will be left to a separate venue. Hemp is a neglected and valuable agronomic crop. It was nearly lost, but was returned to our notice through the auspices of persons mostly concerned with the black sheep cousin by which it was shunned. These persons have alleged hanky-panky in the events of 1937. There certainly was. All in all, the words of Auden best sum up that "low, dishonest decade."


5. Hemp is Not Marijuana

Since now we are suffering fiber shortages, we come back to hemp. And those who want to grow it find they have a problem: Someone says the kids are going to steal the crop and smoke it to get high.

What are the facts?

Psychoactive varieties of Cannabis originated in tropical Asia and probably trace to northern India where they were valued by certain religious sects. Medicinal uses were well known to classical pharmacology. The herbal of Chinese Emperor Shen Nung from 2737BC, appears to be the first pharmacological citation. In the nineteenth century, recreational use was popular among an talented, though debauched, group of European literati known as the Club de Haschishins. By the early decades of the twentieth century use by certain minorites in the US had begun to draw attention. Its popularity among the artist-musician-bohemian set has been well documented.34

The cannabis used medicinally and recreationally in the US in the early decades of this centurycame from the West Indies and Mexico. Chinese and European varieties of fiber hemp lack the biochemistry, the enzymatic machinery, for efficient conversion of the cannabinoid precursor into psychoactive tetrahydrocannibinol (THC).35Germplasm with this capability originated in tropical zones where THC may serve an adaptive role by protecting the plant tissue from intense sunlight and damaging UV radiation.36

As early as 1889, botanist and plant explorer George Watt had written of the distinction between types of Cannabis:

A few plants such as the potato, tomato, poppy and hemp seem to have the power of growing with equal luxuriance under almost any climatic condition, changing or modifying some important function as if to adapt themselves to the altered circumstance. As remarked, hemp is perhaps the most notable example of this; hence, it produces a valuable fibre in Europe, while showing little or no tendency to produce the narcotic principle which in Asia constitutes its chief value.37

The Marihuana Tax Act of 1937 requires all growers, importers and processors of hemp to register and be licensed. As a result of growing public opposition to the cultivation of this drug plant [italics added], the continuation of hemp culture in the United States may depend upon eliminating as much as possible of the active drug principle from the plant. Preliminary tests indicate a possibility of ultimately obtaining a hemp variety with little or no active drug. Research on this problem is actively under way.38

All research on Cannabis in the US since 1937 has been predicated on, and has served to reinforce, the misinformation that all Cannabis is psychoactive and a threat to society requiring elaborate and expensive eradication and suppression efforts. Much of basic research funded through the National Institutes of Drug Abuse has been directed at elucidating the pathway of THC synthesis and designing synthetic analogs. There are now THC analogs reported to have 500 times the potency of natural THC so we can be confident that a new, potent, illicit drug will soon find its way to the streets, as occurred with the coca plant.

The forced association of hemp with marijuana has continued to the present, in spite of the plethora of information to the contrary. Cannabis expert Robert C. Clarke has graphically depicted the variation for psychoactive potential within the genus using the ratio of THC to CBD as developed by Small, et al. Figure 3. The Type 2 Cannabis varieties from sites in Minnesota, Iowa and Germany, easily separate out as those with THC/CBD ratios less than 1.

FIGURE 3: Type 1 (medicinal, psychoactive, herbal, drug) vs Type 2 (fiber) Cannabis accessions classified by ratio of THC to CBD and related to point of origin. Reproduced from Clark (1981).39

Clarke and Pate (1994) succinctly stated the difference between Type 1 and Type 2 Cannabis:

It is not feasible to 'get high' on hemp, and most marijuana produces very little low-quality fiber. Hemp should never be confused with marijuana, as their roles cannot be reversed.40

Canadian researcher, Ernest Small has written a two volume study of The Species Problem in Cannabis41 based on his extensive exploration of the subject. He summarizes the debate:

Lamarck was apparently only vaguely aware that the distinction he was drawing in Cannabis reflected the fact that this genus, through domestication, has been subjected to intensive disruptive selection, which has produced two kinds of plant. On the one hand, plants have been domesticated for the valuable phloem fibres in the bast. To maximize quality and obtainability of these fibres, man has selected plants which are tall, relatively unbranched, with long internodes, and with a relatively hollow stem. Lamarck termed such plants C. sativa. Such domesticated plants have been characteristically grown in Europe, northern Asia, and North America. "Wild" plants of such northern areas of the world tend to be somewhat similar, either because they have escaped back to wild existence from cultivated fibre strains, or because they have been influenced by hybridization with such domesticated strains. In contrast, man has also selected cannabis plants for the ability to produce an inebriant. Cannabis synthesizes a resin in epidermal glands which are abundant on the leaves and flowering parts of the plant. This resin comprises a class of terpenoid chemicals called the cannabinoids. Two are of particular importance: the non-intoxicant cannabidiol (CBD) and the highly intoxicant 9-tetrahydrocannabinol (THC)....Predominance of CBD characterizes the resin of fibre strains, and also strains selected for the valuable oil content of the fruits (achenes). Predominance of THC characterizes "narcotic" strains of Cannabis. Drug strains do not exhibit features related to harvesting the fibre. They are often fairly short, possess short internodes, are highly branched, and have comparatively woody stems. It was this type of plant that Lamarck named C. indica. Such plants are characteristic of southern Asia and Africa where Cannabis has been used for millenia as a source of the drug. "Wild" plants of such relatively southern areas of the world tend to be similar, either because they have escaped back to wild existence from drug strains, or because they have been influenced by hybridization with such domesticated strains.

End of discussion.

6. The "Other" Industry

Although by 1930 the traditional hemp industry in Wisconsin had contracted to miniscule acreage, beginning around 1934, there was a marked expansion in hemp acreage elsewhere (Table 1). The circumstances which would make it expedient to call hemp "marijuana" can only be understood if one is cognizant of this development. But, again, in keeping with our immediate purpose, we will not undertake here to complete the picture of all the humongous forces at play on that historical stage and how hemp became "star- crossed" in the drama.

As we see in TABLE 1, there was a sudden dramatic expansion in hemp acreage beginning in the early thirties. (Table 1 data raise some questions for which we do not currently have answers. Hemp yields, computed from these data, were relatively constant at around half-a-ton per acre until the period 1914-1918. Was this a reflection of USDA hemp improvement activity, and why did it decline again? Also, why does the acreage expansion in the thirties not report increased fiber production?)


5-Year Period

Hemp Grown

Fiber Produced

Fiber Imported




No Record




No Record




No Record













































The relevance of this new industry to our discussion of hemp is that it was here that the "chemurgic" possibilities of the crop were explored. It was this other, new, "unorthodox" industry that was the focus of the enforcement of the Marihuana Tax Act by the Treasury Department's Federal Bureau of Narcotics. The law was not equally enforced against all hemp producing area. This fact betrays a hidden agenda on someone's part. The industry in Wisconsin limped along until 1958. It was not bothered by the FBN in the thirties, and contrary to current popular opinion, the tax was not prohibitive.

The chemurgic industry had its roots in German hemp technology which had advanced markedly in the preceding decades.

"Cut off from the overseas supplies of cotton, jute, sisal and ramie, the German governments reconsidered hemp and supported improvements to cultivation, harvesting and processing technologies. For example, the development of the so-called cottonization process allowed production of a short fiber, high quality substitute from the long hemp fibers. During the 1920s the substitution of all cotton imports by cottonized domestic hemp was seriously discussed."43

The decorticator was developed in Germany and it was there that the chemurgic idea of using hemp as a cellulose source was seriously researched in the laboratories of I. G. Farben.

The industry which emerged in the US starting around 1933 were Amhempco, Inc. in Danville, Illinois; the National Cellulose Corporation in Mankato, Minnesota (later renamed the Hemp Chemical Corporation); Chempco, Inc. and Cannabis, Inc. in Winona, Minnesota.

A picture of the new hemp industry seen from "street-level" comes to us from an article in the Winona (MN) Republican-Herald, December 31, 1937.

The plant manager at Chempco explains their interest in the hurds as a source of cellulose for making plastics: cellulose acetate, also known as rayon acetate. Rayon, until that very year, 1937, the only significant synthetic fiber, was made with cellulose from cotton linters, the short, leftover, pure cellulose strands of cotton fiber. Cellulose from any source can be used, potentially. Wood was becoming the most significant cellulose source at this same time as new chemical intensive pulping processes had recently been invented which led to the development of industries in the South pulping southern pines.

This article appeared on New Year's eve 1937. It was a year which saw the passage of the Marihuana Tax Act and the patenting of nylon, the first non-cellulose synthetic fiber, made from petroleum hydrocarbons. It is also the year nylon's inventor, Wallace Carothers, committed suicide. And DuPont, Britain's ICI and Germany's IG Farben were negotiating the division of Argentina's La Cellulosa chemical company.

This was also the eve of the year when the new Agricultural Adjustment Act, which paid farmers not to produce, would establish four regional laboratories to explore new uses for agricultural produce, a concept inspired by the Chemurgy Movement. The proponents of Chemurgy suggested that the farm crisis could be alleviated by mandating the use of agricultural products in the production of synthetic chemical products. "Cellulose," Williams Haynes observe44, "is the great chemurgic crop-that is, a crop grown for industrial use, not for food." And, he suggested, "The chemical that grows is an ideal raw material out of which to build a global economy of abundance for all mankind."

Another thing you can make from cellulose is nitrocellulose, smokeless gunpowder. It was the eve of the Second World War.

7. Then What?

It is sometimes suggested that the Marihuana Tax Act was prohibitive and forced the demise of the industry. In fact, it was minimal. People involved with scientific and medical studies paid $1 for a license; those in agriculture and industry were to pay $3, although in Wisconsin reportedly farmers also only paid a dollar. Seed handlers paid a little more and had extra paper work. Willard Rens, the "Hemp King of Wisconsin" closed the doors on that industry in 1958. He told the author that the narcotics agents never visited his company. It was simply a matter of filling out the forms and sending off the money.

Recent investigations have revealed that the 1937 Marihuana Tax Act was used specifically against the short-lived ventures in Minnesota and Illinois. Dr. Edmond A. Schlesselman, son of Dr. J. T. Schlesselman, the Mankato, Minnesota, eye, ear, nose and throat doctor who was President of Cannabis, Inc, was 30 years old when his father's company was hassled by the FBN. He tells that "they had to get an agent for every step. It just made it unworkable."

The reader has a right to wonder why these companies were made the object of FBN harassment when the industry in Wisconsin, as Andrew Wright said, "are not concerned about this last law [The Marihuana Tax Act] because I believe they were given a very square deal in the national legislation on the matter."45 The myth is still perpetuated that this action was in some way justified because hemp can be used as a drug. Agencies of government still draw substantial taxpayer support predicated on this myth, and, to avoid having to explain that they have lied, the story is advanced that hemp had to be fixed. We are then told that new varieties have been developed which have fixed it so now we can grow it again. Poppycock. There is plenty of evidence that Kentucky hemp never had psychoactive potential. There was nothing to fix.

So the reader may well wonder what was going on then, and what is going on now.

This was not the first time hemp had stood on the verge of marvelous opportunities. Another "lost episode" in hemp's saga is that of George W. Schlichten. This amazing story, unearthed by Donald Wirtshafter, reveals the invention of a machine, called a decorticator just after WW1. Inventor Schlichten, a German immigrant, had perfected a process for bast fiber separation which handled unretted stalk and produced a superior, lustrous, white, hemp fiber. A witness said of it: "I have seen a wonderful, yet simple, invention. I believe it will revolutionize many of the processes of feeding, clothing and supplying other wants of mankind."46

In 1917, after spending $400,000 developing his decorticator, Schlichten was setting up in California to process hemp. Then, Schlichten and his machine quietly fade into history. It is said a fire destroyed everything.

Schlichten's decorticator apparently worked by the differential stretching of the fiber with a series of complicated gears and fluted rollers which broke the pectin bond between fiber and woody core.

The machine was lost, but a man named F. E. Holton, who appears seemingly out of nowhere, promoting hemp in Minnesota in the mid-thirties, also had a machine he called a decorticator. Together with Dr. Schlesselman, and local bank president, Harry Pribnow, he formed Cannabis, Inc. In the course of other comments at the 1938 Marihuana Conference (which was also attended by Andrew Wright), Dr. B. B. Robinson of the USDA's Division of Cotton and Other Fibers, made an oblique reference to the passing of the Minnesota companies:

"Another argument for the hemp industry is the adaptability of the hemp plant to various regions of the country and because of suitability for mechanical handling, and these are some of the reasons why the office with which I am connected in the Department of Agriculure is interested in seeing this small nucleus of hemp industry continued each year until it is capable of supporting itself. I am speaking more of the industry in Wisconsin rather than the promotional attempts to grow hemp in Minnesota which one might speak of as unorthodox processing. But this industry we have [Wisconsin] is capable at the present time of supporting itself if public opinion does not force it to be shut down, or additional restrictions hamper it....This past summer, we had 1300 acres of hemp produced commercially in this country, and it has been running about that acreage with the exception that in 1934 and 1935 this acreage appeared in Minnesota, and in 1936 and 1937 we had a big acreage in Illinois, but those were acreages planted, you might say, for other purposes than the ordinary use, for there was an idea of producing fibre as a substitute for wool [celanese rayon] and various things of that nature. Those industries that attempted to do that, for one reason or another, have dropped by the wayside..."47

The reader may well wonder about all this. For those who do, read another book. The complexities of this issue are too great to venture into here.

When Japan cut off access to Phillippine abaca, only the Wisconsin-Kentucky operation remained. Seed supplies were short, but the emergency production of 1942-4 was sufficient to alleviate the fiber crisis. In spite of the approximate $300,000 spent setting up each of the 42 mills built throughout the midwest by the War Hemp Industries Corporation, hemp production collapsed again at the end of the war. The mills were sold off as government surplus shortly after the war ended. Many of these structures are still standing today, as they were built very sturdily. The mills were reportedly designed by Andrew Wright. Whether in Ripon, Wisconsin, or Winchester, Kentucky, they all have the same concrete block construction with curved roof and long drying tunnel. The drying tunnel was heated by burning the leftover hurds.

The rest of the history of hemp, to the present, has little to do with hemp. Our attention has turned to hemp again, at fin de siecle, fin de millenium, as the world experiences fiber shortage, for paper, construction material, insulation and textiles. With recognition of the cotton-chemical complex, consumers are shifting to "green" hempen eco-apparel. And, with rising consciousness, people have begun to question how the government was ever allowed to usurp the ancient right to plant a seed and use the natural harvest (consider Genesis 1:29.). They ask, "Why not hemp?"

A decent respect for the opinions of mankind requires a just response to the question. It was probably beyond Thomas Jefferson's wildest apprehensions about the abuses of government power that it would someday presume jurisdiction over this basic freedom, or the Bill of Rights would surely contain eleven amendments.


Part 2


The current dilemma for North American hemp is that we have lost the germplasm, the machinery and the know-how of raising the crop. But, at the same time, neither is it encumbered by antiquation. It seems fair to expect the crop will find niches heretofore untapped (Figure 5), since environmental impact as a factor in consumer choice is a relatively new phenomenon. The emergence of ISO14000 environmental standards heralds a new paradigm of environmental stewardship surpassing ISO9000 Quality standards in manufacturing. Until recently, the powerful forces in theTwentieth Century which have canalized society into the consumption of synthetic goods have met with little resistance. Perhaps this is changing.

Newly available are two classic references on hemp from studies in the US. Dewey's 1913 USDA Yearbook of Agriculture article on hemp was reproduced in Rosenthal's Hemp Today. Another reference is the 1944 Iowa State Experiment Station Farm Bulletin, P63, "Hemp Production Experiments". This latter publication is the most comprehensive study done in the US on hemp husbandry. Both these sources should be read in their entirety.

The farmer who wishes to grow this crop must determine what his/her intended use is for the harvested product. Today, the potential uses for hemp are more numerous than have previously been recognized, and, to varying degrees, each should be considered an individual crop with specific varieties, seeding rates and management. If seed is the crop, and stem is the byproduct (suitable for paper and composite lumber, not for textiles), the grower should seek a seed (monoecious) variety. But if fine textiles are the goal, and the crop will be taken before flowering, a Hungarian kompolti variety is recommended. Likewise, if the market for the hemp stalk is replacing wood chips in fiberboard, it may well be that a high percentage of core (smaller hollow) is preferable and breeding selection will develop appropriate varieties. The feral germplasm in North America may be particularly valuable in this case.

The hurds-the leftover, broken, inner woody core-have been something of a nuisance historically. When stems were broken in the field by moving the break from shock to shock, the hurds quickly composted into the soil. The Wisconsin industry used the hurds to heat the drying tunnel through which the stems moved on their way to the decorticator. Hurds were reportedly still leftover in abundance and were given away to farmers for animal bedding. Today, Hemcore in Britain has found a market selling hurds for horse bedding: it composts faster than straw or wood chips, it is four times more absorbent and it does not tangle into the animal's hair. Animal bedding is only one of the uses rediscovered or newly invented for this former byproduct. Cellulose, such as the Minnesota companies were intending in the 1930s, is another. In France, Isochanvre is a building material made by mixing hemp hurds and plaster. It is seven times lighter than concrete and has superior thermal and acoustic insulating properties. But in France, hurds are only available as a byproduct from the hemp industry licensed for fiber production,limiting the expansion of this usage.

1. Hemp As Organic Weed Control

The first synthetic herbicides appeared in the 1930s. Since that time the chemical dependency of farms has been progressively secured. Non-chemical approaches have generally been relegated to "fringe" associations. Recently though, the concept of sustainability in agriculture has been finding greater academic support. A component of sustainability is responsible use of agchemicals, with emphasis on reduction in favor of "organic" methodologies. Hemp has an important role to play in sustainable and organic agriculture systems because it can clean fields of weeds.

In his textbook, Modern Weed Control, A. S. Crafts cites as potential weed smothering crops: millet, Sudan grass, sweet clover, sunflower, rape, barley, rye, reed canary grass, crested wheatgrass, sorghums, buckwheat, soybeans, alfalfa, cowpeas, clovers, hemp, Jerusalem artichoke, and ensilage corn. Of these only one, hemp, can be taken seriously as an adequate weed controlling competitive crop. The testimonials to hemp-as-weed-control are legion. Some examples:

" is certain that hemp contributes more than any other crop towards repairing the damage done by its own growth through the return of the leaves to the soil, besides other matters while it is undergoing the process of retting. Hemp is an admirable weed killer and in flax countries is sometimes employed as a crop in rotation, to precede flax because it puts the soil in so good condition." -Charles Dodge, Director, Office of Fiber Investigation, 1890.

"There will be little trouble with weeds if the first crop is well destroyed by the spring plowing, for hemp generally occupies all the ground giving weeds but little chance to intrude....In proof of this, a North River farmer a few years ago made the statement that thistles heretofore had mastered him in a certain field, but after sowing it with hemp not a thistle survived, and while ridding his land of this pest the hemp yielded him nearly $60 per acre where previously nothing valuable could be produced." -C. Dodge, Hemp Culture, USDA Yearbook of Agriculture, 1895

"Hemp prevents the growth of weeds and other vegetation which would be found on such soils in most other crops or after others are laid by, and its cultivation also seems to make the soil more uniform in character." -Lyster Dewey, The Hemp Industry in the United States, USDA Yearbook of Agriculture, 1901

"Very few of the common weeds troublesome on the farm can survive the dense shade of a good crop of hemp...In one 4-acre field in Vernon County, Wis., where Canada thistles were very thick, fully 95 per cent of the thistles were killed...." Lyster Dewey, Hemp. USDA Yearbook of Agriculture, 1913.

"Hemp has been demonstrated to be the best smother crop for assisting in the eradication of quack grass and Canada thistles....At Waupon in 1911 the hemp was grown on land badly infested with quack grass, and in spite of an unfavorable season a yield of 2,100 pounds of fiber to the acre was obtained and the quack grass was practically destroyed." -Andrew Wright, Wisconsin's Hemp Industry, 1918.

"Hemp has been recommended as a weed control crop. Its dense, tall growth helps to kill out many common weeds. The noxious bindweed, a member of the morning glory family is checked to some extent by hemp."-B. B. Robinson, Hemp, USDA Agric Bull #1453, 1943

"Among the species studied, the hemp species proved itself to be the best in fiber production. This plant was all the more interesting owing to its low fertilization requirements, and its ability to grow without being irrigated and without chemicals, whether it be for weed or pest control." Barriere, et al. 1994 48

"Hemp grows quickly, soon covers the ground and chokes out the weeds. So weed control is not necessary." -Eddy A. A. de Maeyer. 1994 54

"In an age increasingly interested in sustainable agriculture and crop diversification, hemp offers some attractive possibilities. It is exceptionally disease and herbivore-resistant, can be easily grown in a wide range of agricultural systems and is an excellent rotation crop which eliminates weeds." --Gordon Reichert, 1994. 49

In Holland, Lotz, et al. tested hemp's superior weed suppressing ability (Figure 1) against four other cropping situations in a controlled experimental setting. The target weed was yellow nutgrass (Cyperus esculentus), a weed also common in the US, which propagates by tubers and is difficult to control. The authors conclude,

"...hemp was the most competitive crop in this study. Selecting this crop in a rotation will cause the strongest population reduction ofC. esculentus on infested farmland. This control option of hemp against harmful weeds as C. esculentus is an attendant benefit of the introduction of hemp as a commercial crop."50

Although the historical record contains testimonials to hemp's rather benign impact on the land, and instances where it has been grown in monoculture for over twenty years, it is not recommended that hemp be grown repeatedly on the same plot. Two successive years of hemp, if properly fertilized, will not be injurious and in cases of recalcitrant weeds, may be required to clean the fields. A favorable rotation includes a nitrogen fixer alternating with hemp and row crops or small grains. Hemp will do well in rotation with alfalfa and corn. The old-timer's rule of thumb was, "any land that grows a good crop of corn will grow good hemp.quot;

Kok and Coenen (1994) reported that hemp was a poor host for Meloidogyne chitwoodii, a nematode pest. Hemp grown on infested acreage would not support proliferation of this pest.51 In a similar vein, Mankowski, et al. (1994) reported growing hemp on land polluted with heavy metals. The metals were taken up into roots and stem.52

2. Agronomics

Seed Variety

In a sophisticated, industrial society in which hemp is a cropping option on equal footing with all others (corn, soybean, cotton, etc.), varieties will be bred by commercial plant breeders for specific uses. Multi-purpose varieties may also be bred, although it is often the case that such varieties fail to optimize their primary economic traits.

At this stage, available varieties have been bred for fiber. Broadly classified, hemp varieties are either monoecious or dioecious, that is having the sexes on the same or separate plants, respectively. Monoecious varieties have been bred in France, primarily. The advantage is greater uniformity and increased yield of seed. Monoecious varieties are best where a dual usage-fiber and seed-is desired. Bosca, the great Hungarian hemp breeder, has pointed out that monoecious varieties suffer a degree of inbreeding (perhaps 20%) which would decrease potential.53

Current legal encumberances to the hemp crop tend to mitigate in favor of French varieties. Nonetheless, varieties from Hungary, Poland and the Ukraine should be considered as well. Only in Hungary have hybrid varieties been developed. Elsewhere, the eastern European hemps are dioecious, open-pollinated synthetics, rather like the type of corn (maize) grown prior to the advent of hybridization in the early decades of this century. The significance of this relates to the manner in which the seed supply is reproduced. Hybrid varieties require fairly elaborate operations to maintain the parent materials which are crossed to create the hybrid variety planted by the farmer. Considerable research goes into identifying specific genotypes which, when hybridized, combine genetically for optimum productivity. However, the farmer must depend on an industry which manages the seed production. This dependence, decried by some, seems to have served farmers in the case of corn. It is generally true that hybrid varieties are made if manipulation of pollination is practical. The corn plant's morphology, for instance, allows easy emasculation (detassling).

Male hemp plants can be physically removed from a dioecious population serving as seed parent. Certain Hungarian hemp hybrids are made using a technique which employs the ability to make unisexual (female) populations which can function in a manner analogous to male-sterility to facilitate crossing. Currently, hemp "hybrids" grown by the farmer are acutally the F2, or second generation. Higher yields result, but uniformity, such as we are accustomed to in F1 corn hybrids, will be lacking. So far hemp has been recalcitrant to inbreeding (so was corn, in the early stages). Hemp varieties are therefore inherently variable. Because of genetic segregation, subsequent generations from that immediately following hybridization (F1) are even more variable. Thus, the trade- off for performance is the need to purchase planting seed each year. Use of "bin-run" seed is inadvisable from this perspective.At present, this matters little, as it is probable that farmers growing hemp in the near future will be required to obtain their seed from certified seed growers to assure compliance with THC regulation. This hang-up will no doubt ultimately be recognized as silly, but while competing interests control public policy, we will be forced to accommodate. (These competing interests will attempt to entangle hemp farming in a plethora of redtape, to strangle it. Excessive accommodation is not recommended.)

One promising system has been suggested in Kentucky and will be discussed later.

If the variety is not hybrid, the owner of the variety, such as the various bast fiber institutes of Eastern Europe, is likely to require the buyer to sign a contract promising not to reproduce it (save seed for replanting or sale). Germplasm is handled like software in these modern times, and as such it is private property. Right to ownership of germplasm assures the breeder that research costs can be recouped. Today, it is even possible to patent seed varieties. Like it or not, such developments can be anticipated for hemp as it becomes a more sophisticated crop.

There are many hemps which are excluded by current regulations, including some superior Hungarian hybrids as well as hemps which have not sought inclusion, such as the Chinese and Chilean hemps. The 0.3% THC threshold was established more on political than scientific grounds and is in need of serious reevaluation. Countries newly opening to hemp should not adapt this outmoded criterion without assessing the implications it has for germplasm options.

Because hemp varieties adapted to North America have been lost, the North American farmer will, for the near-term, be required to import seed. This is only one of the barriers to be faced. When importing seed, the buyer must ensure that the seed is accompanied by the appropriate forms. First of these is the phytosanitary certificate, which the seller should provide. This certificate indicates that the seed has been inspected and is free of disease organisms which could introduce a disease to the indigenous crop (irony aside). There may also be a requirement for the "Orange International Seedlot Certificate." Again, it is the responsibility of the seller to make sure this form accompanies the seed. It is important for the buyer to remind the seller of these requirements as some hempseed sources in Eastern Europe may be unfamiliar with these requirements.

The expectant hemp farmer is advised that the rigmarole implicit in having to import the seed necessitates initiating the seed acquisition well in advance.

Land Preparation

Hemp is not a crop to be grown haphazardly or sloppily. Many reports indicate an intimate relationship between fiber quality and the character of the land. Bear in mind that hemp varieties do not have the genetic uniformity that North American farmers are accustomed to in their F1-hybrid corn varieties or their wheat and soybeans. In the case of corn, all plants of a given variety are genetically the same because the hybrids are created from carefully bred and selected "inbred lines" which are genetically homozygous (lacking variation). Soybean and wheat are self-pollinating crops which are themselves inbred and homozygous. A variety of a self- pollinated crop generally traces back to a superior individual plant selection which was increased for commercial distribution.

Hemp, as already mentioned, inbreeds with difficulty. The separation of the sexes ensures that individual plants do not mate with themselves. When hemp is forced to inbreed, the vigor and fecundity of progenies declines rapidly and the lineage is quickly extinguished. This then means that varieties are maintained as pools of genetic variation, rather like a race, or regionalism. Within a generally recognizable type, a wide range of variation is found from individual to individual.


One consequence of the genetic variation among individual plants in the field is that some will have greater vigor than others just by the random assortment of genes each generation. Given the opportunity, these plants can outgrow their weaker neighbors, crowding them out and leading to great irregularity in the crop. Preparation of the land is always highly emphasized in standard discussions of hemp culture. Unevenness in the field due to improper tillage or fertilization will contribute to undesirable plant to plant variation. Plowing should be deep, followed by harrowing until a smooth, level bed is developed. Excessive clumping of soil, dead furrows, recalcitrant weed patches and uneven fertility are to be assiduously avoided. Leaving manure in piles for later spreading for instance, can cause spots of hyperfertility where plants will grow excessively. Care in preparation of the seed bed is probably the single most significant factor in the production of quality hemp fiber. If the field has had a bad weed infestation, it is important to fully disk down the weeds so that hemp will get a jump on them. Once hemp is established, it will generally suppress weeds, as we have repeatedly emphasized.

Fertilization is a complicated issue when it comes to hemp. The reader is referred for details to the appended Iowa State Bulletin. If the hemp is being grown for fiber, quality features are as important as total biomass yield. Pouring on the nitrogen will increase yield, this has been adequately demonstrated. But too much nitrogen leads to coarse, rank growth. The best source of nitrogen is the prior growth of a nitrogen fixing legume, preferably alfalfa or clover and application of manure. The authors of the bulletin indicate that soybeans are less effective at providing nitrogen to a following hemp crop. (See Figures 14 & 17 in the bulletin.) Hessler54 concurred with the effect of over-fertilization. Furthermore, he demonstrated that "a definitely weaker fiber was produced where fertilizers containing nitrogen were used." Nitrogen was found to increase the protein content of the stem to the detriment of strength. The weakest samples had the highest nitrogen content. Van der Werf55 demonstrated that excess nitrogen fertilization increased interplant competition leading to greater self-thinning in the crop and uneven growth.

Dempsey, in his classic work, Fiber Crops,56 presents a table indicating that hemp's removal of nutrients greatly exceeds that of maize and other grains. Since this table has been reproduced in the recent, popular, AgCanada BiWeekly Bulletin: Hemp,57. Hemp, it is important to point out that the maize yields represented in the table are unrealistically low for modern farming. The general rule-of- thumb for corn farmers is "a pound of N for every bushel of expected yield." At such rates, and, moreover, considering that the majority of N hemp uses for growth can be returned to the soil, the soil budget for hemp is even more attractive.

The Iowa Bulletin indicates that inorganic fertilizer of the same kind commonly used for corn works adequtely for hemp. Kozlowski, in Poland, recommends 80-110lbs/acre available nitrogen (N); 60-90 phosphorus (P); 135-160 potassium (K); 14-18 calcium (CaO). This considerable range leaves much open to the farmer's experimentation. Fiber and seed crops are handled differently:

ratio N:P:K 1:0.7:1.5 (fiber) 1:0.8: 1 (seed)58

Given its weed control function, hemp integrates well into "organic" agriculture. Hemp is reported to perform best on well- manured soils with high organic matter (well-drained). Naturally, the soil nutrient status should be thoroughly tested and periodically monitored. Although hemp is reported to accept soil acidity as low as pH 5.5, neutral pH is recommended. Lime accordingly. Hemp may be drilled or broadcast. Drilling is recommended for uniformity. A grain drill or modified alfalfa seeder can be used. Planting depth is between 0.5 and 1.0 inch, although greater depths are occasionally recommended (up to 2 inches in Poland). Row spacing for fiber should be four to seven inches, 50-60lbs/acre (a bushel -44lbs- and a peck). (Variability in germination can be a problem among hemp seedlots. The grower is well advised to test a sample and adjust planting rate accordingly, at least until the seed industry takes responsibility for this crop.)

The seed crop is planted much less densely (the seed crop is not a weed controller) at about twenty-inch spacing, approximately 10lbs/acre. A bushel of Kentucky hemp seed weighed 44 pounds. There are circumstances, for instance, the production of fine, flaxen, water-retted textile fiber, which warrant planting at much higher rates, hundreds of pounds of seed to the acre. There is much opportunity for experimentation by individual farmers to determine optimium practice in their specific environment.

Hemp can be planted early. Recommended soil temperature for planting is 8-10°C. In Wisconsin the crop was planted before corn. It can generally be the first crop seeded. Darsie, et al. (1914), reported the temperature of the emerging hemp seed to be the highest of the plants they surveyed.59 It generates its own heat metabolizing its seed oil. This early emergence character of hemp is a component of its weed suppression.

Another positive attribute of the crop is that once it is planted, no further husbandry is required until harvest. This "plant it/harvest it" aspect of the crop reduces energy consumption as well as soil compaction from passes by spraying and cultivating equipment. Although in damp climates the crop can suffer from the Botryis leaf fungus, treatment is not deamed worthwhile. Similarly, European corn borer, a pest of corn, has been reported to occasionally burrow a hemp stalk. But no insects bother the crop sufficiently to warrant remediation.

Researchers in Manitoba in 1995 had some negative experiences both with insects and weeds. The crop was planted late because the permitting redtape delayed seed shipments. Furthermore the varieties were imported from Eastern Europe since our own adapted material is no longer available. This is not an uber-crop impervious to all the vagaries of the environment. Properly managed adapted varieties throughout the world have a very positive track record on pest problems.

Birds, on the other hand, can be a serious problem in the seed crop. Birds love hempseed. Good luck.


This is where things start getting more complicated.

The Kentucky Hemp Grower's Co-operative Association, recently reincarnated from its 1942 charter, is ahead of the ball on the practical aspects of organizing the production of this crop. Their system borrows from the tobacco model, familiar to most farmers in the state.In their model, all aspects of the crop would be handled through the co-op.

Farmers plant seed provided by the co-op; this provides for control of genotype. The co-op manages issues related to hemp variety evaluation and certification in compliance with legalities. Just as the cannery specifies the pea variety to the farmer, so does the hemp co-op allot acreages for specific hemps. The co-op forward contracts with fiber end-users for the needed production. Acreages are alloted accordingly among co-op member farmers. Marketing of the fiber is handled through the co-op. The crop can only be grown under contract to the co-op. It cannot be grown "on spec." Supply/demand relationships are managed to maintain profitability for the farmer. A grower must be a member of the co-op and bonded. Members found violating variety control regulations lose their allotment and forfeit their bond.

In the Kentucky Co-op model, conceived for Kentucky conditions, farmers hold the fiber on-farm, probably in a baled form, and disperse it to the mills over the year, providing steady income. This intelligent system handles the objections so often raised to obstruct this crop: the supposed fear that hemp fields will be used to sequester marijuana plants. Under this system farmers have powerful incentive not to engage in planting of illicit varieties of Cannabis. (Hemp fields are not good places to grow horticultural varieties of Cannabis for the following reasons: 1) Hemp for fiber is cut before plants flower; 2) plant density is high in the agronomic setting; 3) if flowering occurred, abundant pollen would reduce the quality of the herb; herb farmers will want to keep their plants away from hemp fields; high test genetic strains will be degraded by contamination with fiber hemp pollen.60)

The Kentucky system provides for total integration of crop production and marketing. No one will be growing the crop who does not have a permit and the trail will be complete from seed through the final disposal of the fiber. Authorities can know where and by whom the crop is being produced. If a person is in possession of Cannabis who is not in the co-op system, they will be guilty of illegal possession, regardless of THC assay. The co-op will police its membership, obviating the need for complicated and expensive fielding testing of farmers' crops.

Given a system operating in this way, the specific technical issues associated with harvesting and post-harvest handling of the crop will be determined by the co-op organization in accordance with the intended end use. Such specialized harvesting equipment as is needed will likely also be arranged through the co-op and shared.


Seed harvest can be accomplished with a grain harvester with appropriately sized screens. European and Soviet manufacturers have designed combine harvestors for hemp which remove seed and bundle the stem simultaneously. The great expense of such machines necessitates a co-op organization of growers.


Fiber harvest is a whole new matter. Harvest technicalities have nearly done-in the fiber crop at times in the foretold history. This topic could well occupy an entire tome; our treatment can only sketch the subject. First issue: how will the crop be retted? Dew or water; or unretted decortication or sonic explosion?

[in progresso]


*Plant Breeding & Genetics, Univ of MN. The author was Director of the Hawaii Industrial Hemp Project, 1999-2003.



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