INDUSTRIAL HEMP FARMING: HISTORY AND PRACTICE
A HISTORICAL SKETCH OF HEMP FARMING AND INDUSTRY
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. which are horticultural, not
agronomic crops and which 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 twenty-eighth century BC. The wild Cannabis ancestor
is believed to have grown somewhere in a general area between
western China and the eastern Caucasus, north of the Hindu Kush.
This wild ancestor is not found today.
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 of
the crop. Flax, having a lower lignin content in the fiber, was for
centuries the premier fiber for 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 antebellum America, hemp homespun—called "Kentucky jeans"—
was commonly used to clothe the slave population.
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
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. George Washington admonished, "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.
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
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
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
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
coolie 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
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.
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
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
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,
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.
As the nation expanded, so did its government. 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
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
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
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
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
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 191317, 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 ( hemp stem image), but that of Kentucky
hemp was apparently superior since specific attention is drawn to
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
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
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
another 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
In spite of 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
"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.
Fiber is a fungible commodity. Fibers 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. (Fiber
Wars:The Extinction of Kentucky Hemp 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
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."
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
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
The cannabis used medicinally and recreationally in the US
came from the West Indies and Mexico. Chinese and European
varieties of fiber hemp lack the biochemistry, the enzymatic
machinery, for efficient conversion of the cannabidiol (CBG)
precursor into psychoactive tetrahydrocannibinol (THC).35
Germplasm 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 1). 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 1: 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
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
Canadian researcher, Ernest Small has written a two volume
study of "The Species Problem in Cannabis"41 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
End of discussion.
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?)
TABLE 1. PRODUCTION, ACREAGE, AND IMPORT OF HEMP IN UNITED
5-Year Period Hemp Grown Fiber Produced Fiber Imported
(acres) (tons) (tons)
1876-1880 15,000 7,000 No Record
1881-1885 11,000 5,000 No Record
1886-1890 16,000 7,500 No Record
1891-1895 11,000 5,000 4,500
1896-1900 10,000 4,500 5,000
1901-1905 12,000 5,500 5,000
1906-1910 10,000 4,500 6,000
1911-1913 10,000 4,500 6,000
1914-1918 10,500 8,500 5,000
1919-1923 8,600 3,800 4,000
1924-1928 4,300 1,800 2,000
1929-1933 1,200 500 1,000
1934-1938 7,100 600 740
* These figures are from U.S. Dept. Agr. Bull. : Hemp, Its Production
and Use as a Fiber Crop."
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 which 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
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
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. Wood was another source. Cellulose from any source can be
Another thing you can make from cellulose is nitrocellulose,
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
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 observed44, "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."
It was the eve of the Second World War.
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 paid $3; 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, Mankato, MN, eye, ear, nose and throat doctor and
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
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
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
The reader may well wonder about all this. For those who do,
read another book.
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 (Figure 2). 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, 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 fears of government that it would someday presume
jurisdiction over this basic freedom, or the Bill of Rights would
surely contain eleven amendments.
THE CULTURE OF HEMP
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 antequation.
It seems fair to expect the crop will find niches heretofore untapped
(Figure #), since environmental impact as consideration in consumer
choice is a relatively new phenomenon. The emergence of ISO14000
environmental standards heralds a new paradigm surpassing
ISO9000 Quality standards in manufacturing. Powerful forces
canalizing twentieth century society into the consumption of
synthetic goods have, until recently, 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. The 1944
Iowa State Experiment Station Farm Bulletin, P63, "Hemp Production
Experiments" is appended here. 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,
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, thus limiting the expansion of this usage.
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
"...it 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
—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,
"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. 199448
"Hemp grows quickly, soon covers the ground and chokes out the
weeds. So weed control is not necessary." —Eddy A. A. de Maeyer.
"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."
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
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
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, with which it may
be strangled. Excessive accommodation is not recommended.) One
promising system has been suggested in Kentucky and will be
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
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
The expectant hemp farmer is advised that the rigmarole
implicit in having to import the seed necessitates initiating the
seed acquisition well in advance.
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-
pollianted crop generally traces back to a superior individual plant
selection which was increased for commercial distribution.
Hemp has so far been quite recalcitrant to inbreeding. 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. 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 well 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:
1:0.8: 1 (seed)58
Given it’s weed control function, hemp works 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 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 or own
adapted material is no longer available. This is not an uber-crop
impervious to all the viscissitudes of 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
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?
1Small, E. 1979. The Species Problem in Cannabis. Corpus, Canada.
2Hopkins, J. F. 1951. A History of the Hemp Industry in Kentucky.
University of Kentucky Press, Lexington. p.113
3His diaries record the removal of male plants from the hempseed
production fields which has led some to speculate that he was
attempting to grow seedless(high potency) marijuana. This is not the
case. It is common practice in hempseed production to remove all
but a few male plants to reduce competition with the seed bearing
females. There is no evidence George smoked his crop or that the
European fiber hemp he grew had psychoactive potential. Quite the
4Mitchell, R. D. 1973. Agricultural Change and the American
Revolution: A Virginia Case Study. Agricultural History 43:130n.
5Hopkins, J. F. 1951. A History of the Hemp Industry in Kentucky.
University of Kentucky Press, Lexington.
6Bidwell, P. W. and J. I. Falconer. 1941. History of Agriculture in the
Northern United States: 1620-1860. Carnegie Inst. Washington, D.C.
7Presidential Executive Order 12919. June 4, 1994. Oil from the
hempseed has been specified by the military as a lubricant for
8The winter season is represented on the dome of the Paris,
Kentucky, courthouse by a depiction of hemp breaking.
9Hopkins, p. 195
10Dodge, C. A. 1890. The Hemp Industry. USDA Division of
Statistics 1: 64-74.
11Oliver, J. W. 1956. History of American Technology. The Ronald
Press Co. p. 366.
13USDA. 1902. USDA. Yearbk of Agric. p. 23.
14One was at Viroqua, the hometown of the—by then—late Jeremiah
Rusk, and others of lesser note.
15Wright, Andrew. 1918. Wisconsin's Hemp Industry. Wisconsin
Agricultural Experiment Station Bulletin # 293.p. 8.
17The 1913 article has been reproduced and published in E.
Rosenthal,ed., Hemp Today, 1994, Quick American Archives, Oakland,
18Dewey, L. H. 1901. The Hemp Industry in the United States. USDA
Yearbk of Agric. p.554.
19An unfortunate aspect of this introduction appears to have been
the importation of a weed known as "broom-rape" which is parasitic
on hemp roots. The seed is similar in size to hempseed and can be
disseminated with hempseed if care is not taken in the seed fields.
20Dewey, L. H. 1943 Fiber Production in the Western Hemisphere.
USDA Misc. Publ. no. 518.
21Small (1979) contrasts the hollowness of fiber vs non-fiber
(psychoactive) types of Cannabis, which he illustates in this book.
The author (DPW) has confirmed the persistence of the large lumen
in feral stands of Wisconsin hemp which were undergoing
22Bocsa, I. 1995.-------
23USDA. Bureau of Plant Industry. 1917. Report of the Chief. p. 12.
24USDA. Bureau of Plant Industry. 1918. Report of the Chief. p. 28.
Water-retted hemp from Italy was the standard for quality fiber.
25USDA. Bureau of Plant Industry. 1919. Report of the Chief. p. 21.
26USDA. Bureau of Plant Industry. 1920. Report of the Chief. p. 26.A
detailed description of four varieties developed by Lyster Dewey's
federal hemp breeding program is included in the 1927 Yearbook of
27van der Werf, H. 1994. The Crop Physiology of Fibre Hemp.
Wageningen, The Netherlands.
28USDA. 1929. Bureau of Plant Industry, Annual Report. p. 27.
29Dewey, L. H. 1931. Hemp fiber losing ground, despite its valuable
qualities. USDA Yearbk of Agric. p. 285.
30West, D.P. 1994. Fiber Wars: The Extinction of Kentucky Hemp. In,
E. Rosenthal, ed. Hemp Today. Quick American Archives, Oakland CA.
31Hemp and flax—although botanically unrelated—have very similar
fibers and almost identical drying oils (oils high in linolenic acid) in
32Fite, G. C. 1984. Cotton Fields No More: Southern Agriculture
1865-1980. The University of Kentucky Press.
33USDA. 1935. Annual Reports of the Department of Agriculture, p.6.
34Herer, J. 1994. The Emperor Wears No Clothes. Queen of Spades
Publ. Kaplan, J. 1970. Marijuana: The New Prohibition. World Publ. Co.
37Watt, George. 1889. Dictionary of the Economic Products of India.
38USDA. 1938. Bureau of Plant Industry, Annual Report, p. 7.
39Clark, R. C. 1981. Marijuana Botany. Ronin Publ. Berkeley, CA.
Based on Small, E. and H. D. Beckstead. 1973. Cannabinoid phenotypes
in Cannabis sativa. Nature 245:147-148.
40Clarke, R. C. and D. W. Pate. 1994. Medical marijuana. J.
International Hemp Assoc. 1:9.
42Mauersberger, H. R. 1947. Matthews’ Textile Fibers. John Wiley &
Sons, Inc., London.
43Karus, M. and G. Leson. 1994. Hemp research and market
development in Germany. J. International Hemp Assoc. 2:15-19.
44Haynes, Williams. 1958. Cellulose, The Chemical that Grows.
45Andrew Wright, addressing the 1938 Marihuana Conference.
46Wirtshafter, D. 1994. The Schlicten Papers. The Ohio Hempery.
47Marihuana Conference, p. 31.
48From papers delivered at the Conference on Alternative Oilseed
and Fiber Crops for the Cool and Wet Regions of Europe, Wageningen,
The Netherlands, April 7-8, 1994.
49Reichert, G. 1994. Hemp. AgCanada Bi-Weeekly Bulletin 7:23.
50Lotz, L. A., P. R. M. W. Groeneveld, B. Habekotte, and H. van Oene.
1991. Reduction of growth and reproduction of Cyperus esculentus by
specific crops. Weed Research 31:153-160.
51Kok, C. J. and G. C. M. Coenen. 1994. Reproduction of Meloidogyne
chitwoodii on alternative crops. Proc. Alternative oilseed and fibre
crops for cool and wet regions of Europe. Wageningen, The
Netherlands. Ap. 7-8, 1994.
52Mankowski, J., L. Grabowska and P. Baraniecki. Hemp and flax
cultivated on soil polluted with heavy metals. Proc. Alternative
oilseed and fibre crops for cool and wet regions of Europe.
Wageningen, The Netherlands. Ap. 7-8, 1994.
53Bocsa, I. IHA
54Hessler, L. E. 1947. The effect of fertilizers on the chemical
composition and quality of dew-retted hemp fiber. J. Am. Soc. Agron.
55Van der Werf, H. 1994. The Crop Physiology of Hemp. Wageningen.
56 Dempsey, J. M. 1975. Fiber Crops. University of Florida Press.
57Reichert, G. 1994. Hemp. Canadian Bi-Weekly Bulletin --------
58Kozlowski, R. 1995. Bioresource Hemp. Frankfurt, Germany
59Darsie, et al. 1914. Botanical Gazette 38:101.
60Kenaf, which has a rough similarity to the Cannabis leaf, would be
a better crop in which to hide marijuana. They wouldn't cross