This country imports almost all of its fibers except cotton. The
Whitney gin, combined with improved spinning methods, enabled this
country to produce cotton goods so far below the cost of linen that
manufacture practically ceased in the United States. We cannot
produce our fibers at less cost than can other farmers of the world.
Aside from higher cost of labor, we do not get as large a
production. For instance, Yugoslavia, which has the greatest fiber
production per acre in Europe, recently had a yield of 883 lbs.
Comparable figures for other countries are Argentina, 749 lbs.;
Egypt, 616 lbs.; and India, 393 lbs.; while the average yield in
this country is 383 lbs.
To meet world competition profitably, we must improve our methods
all the way from the field to the loom.
Flax is still pulled up by the roots, retted in a pond, dried in
the sun, broken until the fibers separate from the wood, then spun,
and finally bleached with lye from wood ashes, potash from burned
seaweed, or lime. Improvements in tilling, planting, and harvesting
mechanisms have materially helped the large farmers and, to a
certain degree, the smaller ones, but the process from the crop to
the yarn are crude, wasteful, and injurious. Hemp, the strongest
of the vegetable fibers, gives the greatest production per acre and
requires the least attention. It not only requires no weeding, but
also kills off all the weeds and leaves the soil in splendid
condition. This, irrespective of its own monetary value, makes it a desirable
crop to grow.
In climate and cultivation, its requisites are similar to flax,
like flax, should be harvested before it is too ripe. The best time
is when the lower leaves on the stalk wither and the flowers shed
their pollen.
Like flax, the fibers run out where the leaf stems are on the
stalks and are made up of laminated fibers that are held together by
pectose gums. When chemically treated like flax, hemp yields a
beautiful fiber so closely resembling flax that a high-power
microscope is needed to tell the difference--and only then
because in hemp, some of the ends are split. Wetting a few strands
of fiber and holding them suspended will definitely identify the two
because upon drying, flax will be found to turn to the right or
clockwise, and hemp to the left or counterclockwise.
Before [World War I], Russia produced 400,000 tons of hemp, all
of which is still hand-broken and hand-scutched. They now produce
half that quantity and use most of of it themselves, as also does
Italy from whom we had large importations.
In this country, hemp, when planted one bu. per acre, yields
about three tons of dry straw per acre. From 15 to 20 percent of
this is fiber, and 80 to 85 percent is woody material. The rapidly
growing market for cellulose and wood flour for plastics gives good
reason to believe that this hitherto wasted material may prove
sufficiently profitable to pay for the crop, leaving the cost of the
fiber sufficiently low to compete with 500,000 tons of hard fiber
now imported annually.
Hemp being two to three times as strong as any of the hard
fibers, much less weight is required to give the same yardage.
For instance, sisal binder twine of 40-lb. tensile strength runs 450
ft. to the lb. A better twine made of hemp would run 1280 ft. to the
lb. Hemp is not subject to as many kinds of deterioration as are
the tropical fibers, and none of them lasts as long in either fresh
or salt water.
While the theory in the past has been that straw should be cut
when the pollen starts to fly, some of the best fiber handled by
Minnesota hemp people was heavy with seed. This point should be
proved as soon as possible by planting a few acres and then
harvesting the first quarter when the pollen is flying, the second
and third a week or ten days apart, and the last when the seed is
fully matured. These four lots should be kept separate and scutched
and processed separately to detect any difference in the quality and
quantity of the fiber and seed.
Several types of machines are available in this country for
harvesting hemp. One of these was brought out several years ago by
the International Harvester Company. Recently, growers of hemp in
the Middle West have rebuilt regular grain binders for this work.
The rebuilding is not particularly expensive and the machines are
reported to give satisfactory service.
Degumming of hemp is analogous to the treatment given flax. The
shards probably offer slightly more resistance to digestion. On the
other hand, they break down readily upon completion of the digestion
process. And excellent fiber can, therefore, be obtained from
hemp also. Hemp, when treated by aknown chemical process, can be
spun on cotton, wool, and worsted machinery, and has as much
absorbance and wearing quality as linen.
Several types of machines for scutching the hemp stalks are also
on the market. Scutch mills formerly operating in Illinois and
Wisconsin used the system that consisted of a set of eight pairs of
fluted rollers, through which the dried straw was passed to break up
the woody portion. From there, the fiber with adhering shards--or
hurds, as they are called--was transfered by an operator to an
endless-chain conveyor. This carries the fiber past two revolving
single drums in tandem, all having beating blades on their
periphery, which beat off most of the hurds as well as the fibers
that do not run the full length of the stalks. The portion of line
fiber to tow is 50 percent each. Tow or short tangled fiber then
goes to a vibrating cleaner that shakes out some of the hurds. In
Minnesotsa and Illinois, another type has been tried out. This
machine consists of a feeding table which the stalks are placed
horizontally. Conveyor chains carry the stalks along until they are
grasped by a clamping chain that grips them and carries them through
half of the machine.
A pair of intermeshing lawnmower-type beaters are placed at a
45-degree angle to the feeding chain and break the hemp stalks over
the sharp edge of a steel plate, the object being to break the woody
portion of the straw and whip the hurds from the fiber. On the other
side and slightly beyond the first set of lawnmower beaters is
another set, which is placed 90-degrees from the first pair and
whips out the hurds.
The first clamping chain transfers the stalks to another to
scutch the fiber that was under the clamp at the beginning.
Unfortunately, this type of scutcher makes even more tow than the
so-called Wisconsin type. This tow is difficult to reclean because
the hurds are broken into long slivers that tenaciously adhere to
the fiber.
Another type passes the stalks though a series of graduated
fluted rollers. This breaks up the woody portion into hurds about
3/4 inch long, and the fiber then passes on though a series of
reciprocating slotted plates working between stationary slotted
plates.
Adhering hurds are removed from the fiber which continues on a
conveyor to the bailing process. Because no beating of the fiber
against the grain occurs, this type of scutcher makes only line
fiber. This is then processed by the same method as those for flax.
Paint and lacquer manufacturers are interested in hempseed oil
which is a good drying agent. When markets have been developed for
the products now being wasted, seed and hurds, hemp will prove, both
for farmer and the public, the most profitable and desireable crop
that can be grown, and one that will make American mills independent
of importations.
Recent floods and dust storms have given warnings against the
destruction of timber. Possibly, the hitherto waste products of flax
and hemp may yet meet a good part of that need, especially in the
plastic field which is growing by leaps and bounds.
Hemp a profitable crop