THE CULTIVATION OF COCA.[23]
[Footnote 23: From the _Therapeutic Gazette_ (Detroit), January, 1886,
p. 14, and _Pharm. Journ._, 1886, p. 705.]
The most recent account of the cultivation of Coca is given by Henry H.
Rusby, M.D., who, for more than two months, was engaged in the study
of the Coca plant and its products in the districts of Bolivia which
produce the best quality of leaves. He says:—
“For the details concerning cultivation here presented I am chiefly
indebted to Mr. Oscar Lohse, one of the most intelligent cultivators
in this country, and proprietor of the Finca of San Antonio, two
leagues from the town of Caroica, Yungas.
“The district of Caroica may be considered as fitly representing the
remainder of Yungas, and Yungas as representing the principal Coca
districts of this republic. The conditions of soil and climate may be
briefly stated. Proceeding eastward from La Paz, itself somewhat more
than ten thousand feet[24] above the sea, for a distance of four or
five leagues, we reach the summit of the pass over the easternmost
cordillera of the Andes, this cordillera having an average elevation
in this immediate district of perhaps sixteen thousand feet. This
ridge, always more or less snow-covered, cuts off a large portion of
the westward-bound clouds, which are either precipitated in the form
of rain before reaching the summit, or arriving there, are deposited
in the form of snow, and then returned by means of rivulets to the
valleys, chiefly of the eastern slope. It should be noted that in
Northern Peru and Ecuador this cordillera is higher than here, so that
the eastern slope in those regions is more profusely and regularly
watered than here. From this pass, had we a direct road, we could
travel in half a day, so steep is the descent, to the banks of the
Caroica River, having an altitude of only two thousand four hundred
feet. When we have descended to six thousand four hundred feet we
should meet with our first Coca plantations, and after passing the two
thousand foot level we should have left them principally or entirely
behind. Within this four or five thousand feet, then, lie the cocales
of Bolivia. No description can convey a perfect idea of the steepness
of this luxuriant slope. Travel, entirely by riding-animals, is
extremely difficult. There are only occasional places where we can
readily leave the road, and here plantations are established. The
hedge of coffee-plants at the roadside proves on examination to be the
uppermost row of a plantation; and as we peer down among the shrubs
we marvel that anyone can preserve his footing while cultivating or
collecting the coffee. The scenery is, of course, magnificent, and
of a different type, I should think, from that of any other part of
the world. The mountains are too young to have lost to a great extent
their ragged outline, yet softness is imparted by the richness of the
vegetation. We stand among the coca plants and distinctly see another
cocal nearly four thousand feet below us.
[Footnote 24: “I have given altitudes and measurements approximately
in English feet. By the Spanish measurements the altitudes are much
greater.”]
“The cultivated plants of the coca district are coffee, rice, cacao,
sugar cane, tobacco, maize, cotton (the arborescent species), sweet
potatoes, yuccas, and the ordinary garden vegetables. The principal
fruits are oranges, bananas, cocoanuts, lemons (sweet and sour),
citrons, grapes, chirimoyas, alligator pears, tumbas, pomegranates,
grenadillas, figs, papayas, lukmas, melons, and pineapples, the last
just introduced.
“The soil in such a broken country is, of course, very diversified,
ranging from a very light decomposed shale or sandstone to a heavy
blue or chiefly yellow clay.
“The rainy season begins in October, and continues until May or June.
During this time the rains are copious and almost constant. During the
succeeding two months there is scarcely a drop of rain, and during the
next two there are only occasional showers.
“Such are the conditions under which the Coca grows in this section.
“When we come now to consider the methods of cultivation here adopted,
we must be cautious about accepting them as the best, merely because
they are generally followed here. It is to be remembered that the
Bolivian system of agriculture has not received the attention that it
should have had, and that it is very probable that reforms might be
introduced in present methods.
“Nor is it proper to proceed concerning Coca-culture without a few
words concerning what is meant by the ‘best quality’ of Coca-leaves.
To a manufacturing chemist the best quality would mean the quality
that would yield the largest percentage of crystallizable cocaine,
obtainable in the easiest manner, while the same Coca might be
considered for domestic consumption as representing one of the lower
grades. It is highly probable that the amount of cocaine forms no
element in the Indian’s estimate of the quality of Coca, no more than
the percentage of nicotine establishes the quality of a particular
grade of tobacco. Coca-leaves are classed in general by the Indians
as ‘hajas dulces’ (sweet leaves) and ‘hajas amargas’ (bitter leaves).
The former are made sweet by the abundance of alkaloids other than
cocaine. While it is true that a greater abundance of these alkaloids
is usually accompanied by a larger percentage of cocaine also, yet
the variation in the amount of the latter is not so great as in the
former; so that while in the sweet leaves the bitter taste of the
cocaine is masked by the presence of the other alkaloids, in the
bitter leaves its flavour is the predominant one. The presence, then,
of these _sweet alkaloids_, as we may call them, translating the
simple and expressive term of the Indians, determines the domestic
value of the Coca, and all that is known of the best methods of
cultivation is based on the production of the highest percentage of
these alkaloids.[25] Experience may determine that for manufacturing
purposes a very different line of principles of culture should be
followed.
“I have made a large number of assays tending towards elevations,
soils, exposures, seasons, ages of plants, and of leaves, different
varieties, wild and domestic, different parts of the plant, and
various modes of drying and packing. The results will be embodied
in a future monograph, mere passing references being made to them
for the present. I have about concluded that the percentage of the
sweet alkaloids varies inversely as the amount and continuousness of
moisture that the plant receives. Thus, the Peruvian, Ecuadorian,
and Brazilian Coca, which, as I have stated, is much more copiously
and regularly watered than the Bolivian, is markedly inferior,
so that Bolivia regularly exports about one-eighth of her crop to
those countries. I am inclined to think that the greater breadth
and thinness of the northern leaf may be partly due to the greater
water-supply and the consequent greater degree of evaporation. Again,
the Indian always seeks the Coca grown at the higher elevations, where
the humidity is much less and more irregular than in the districts
along the rivers. We are thus obliged, for reasons to be elaborated
in the future, to regard these alkaloids as preserving a sort of a
balance of moisture, by which the plant stores up during the wet
weather a concentrated supply of water, which may be very slowly
yielded up during a time of need.
[Footnote 25: “It is desirable that there should be a more precise
definition of the peculiarities here referred to.—ED. PH. J.”]
“Having thus chosen a high altitude, the next thing is to select a
soil. A rivalry exists between a yellow clay and a hill-side soil rich
in vegetable matter. My assays have yielded the best results (as to
total alkaloids) from soils of the latter class, and I am inclined to
think that those who prefer the former soil do so because it yields a
somewhat larger crop.
“The ground for the nursery-bed is prepared during the latter part
of the dry season by breaking it up very thoroughly to the depth of
a foot or more. The fruits mature during the early part of the rainy
season, December and January. They are red, and consist of a fleshy
outer portion and a shell-like inner portion, which encloses the
single seed. These people suppose that the germ cannot escape from the
shell if planted in its natural condition, and they have continued for
hundreds of years to deposit the seeds as soon as gathered in a shaded
place, in layers an inch or more deep, and covered with a thin layer
of decaying leaves, or similar substance. The heat generated by the
decomposition of the fleshy pericarp serves to induce germination, and
the embryo bursts from its bony covering. This growth unites them in
from eight to fourteen days into a solid mass, which is broken up into
small pieces and planted in furrows in the nursery. In this process
very many of the sprouts are broken off and the plants destroyed. Mr.
Lohse has adopted the plan of sowing the seeds broadcast as soon as
gathered, and covering with a little earth, or, better, a layer of
banana leaves or decaying vegetable matter. Germination requires from
eight to twelve days longer, but all the plants are saved. In either
case, a covering of brush or straw must be placed over the nursery,
at first only three or four inches above the surface, and elevated to
six or seven inches, as the plants grow. Usually this elevation is
repeated once more.
“All this taking place during the rainy season, the plants have
reached a good size before the advent of the dry weather, and so do
not call for any artificial water-supply. Advantage is taken of the
ensuing dry season to clear the land and prepare the ground for the
new cocal. On the manner in which this is done depends much of the
future well-being of the plants. The ground should be thoroughly
powdered to the depth of two, and, if possible, three feet, all roots
and large stones being removed. On these steep slopes it is necessary
to terrace, the terraces being supported by stone walls, the stones
laid dry. The width of the terraces, according to the slope, varies
from several feet, with a number of rows of plants, to much less than
the height of the wall, only a single row of plants being admissible.
It is here generally believed that shade tends to the production of
the best quality of leaves; so the cocales are planted thickly with a
small broad-topped leguminous tree related to the St. John’s bread,
but whose name I cannot at this moment recall. There is no doubt
that this is a mistake. I have made repeated comparative assays of
shade-grown and sun-grown leaves from adjoining plants, and invariably
found the latter much richer in total alkaloids. I judge the custom
to have arisen from two considerations. There is, as I have stated,
a period of two or three months when the plants receive no rain, and
then these trees afford a protection from the fierce heat. Secondly,
shade conduces to the production of a large, smooth, beautiful leaf,
of elegant colour, and thus adds to the _appearance_ of the product.
The terraces being thus prepared, on the advent of the permanent rainy
season, the plants, now from 8 to 12 inches high, are transplanted,
being set from one-half to six inches apart, according to the ideas
of the haciendero. From this time until the first leaves are picked,
the greatest care must be taken to keep the soil thoroughly stirred
and free from weeds. The plants having been transferred in October
or November of one year, the first picking is made in March or April
of the second following year, one year and a half from the time
of transplanting, or two and one-half from the seeds. In case an
insufficient space has been prepared, the remaining plants are often
left until the following year, and then transplanted, the operation
being much more dangerous to the life of the plants.
“The chief danger of picking the leaves earlier than the period
indicated above is not the strain upon the vitality of the young
plant, as many of the leaves drop off themselves, but because it is
almost impossible to avoid breaking off the very tender tips of the
twigs, the result being fatal to many plants. Immediately after this
first picking, fresh leaves develop with great rapidity, and in July
or August of the same year the plant flowers for the first time. The
lovely white flowers, if undisturbed, remain from three to six days;
but from the very first they are dislodged by the slightest jar, the
corolla falling entire, although it is morphologically polypetalous.
The fruit ripens in December and January.
“During the first few years the percentage of alkaloid increases
rapidly, reaching its maximum at or before the age of ten years. At
the age of twenty it begins to diminish, but with extreme slowness,
so that the plants are practically in their prime up to the age of
thirty-five or forty. It is probable that the decline is then due
rather to the exhaustion of the soil than of the vitality of the
plant. Fertilisation of the soil has never been resorted to. It is
probable, as suggested by Mr. Lohse, that as much can be done for the
Coca in this way as has been done for other plants.
“A Coca harvest is called a _mita_, an Indian word meaning a division
or drawing of lots, and there are from three to five in a year,
according to the season. The time of picking is determined solely
by the condition of the leaves. When they have become mature they
turn yellow if in the dry season, and brown if in the rainy, and
within eight days at the outside will fall to the ground and be
lost. As soon as the mita is over, the ground is cleared from weeds,
and, under an ignorant notion that further cleaning is injurious, is
left undisturbed until after the next mita. But Mr. Lohse has tried
the plan of keeping the ground clean, with the result, thus far,
of receiving the next crop in little more than one-half the time
required by his neighbours. No irrigation is resorted to during the
dry season. Although it is possible that good might result, at least
to the welfare of the plant and the size of the crop, I suspect that
after a long time an abundant and steady supply of water would result
in a decrease in the amount of alkaloids. Mr. Lohse has tried the
experiment of mulching at the end of the wet season with a few inches
of banana leaves or other refuse, with excellent effect upon the
plants during the succeeding dry season.
“This plant is subject to only two diseases of any importance. The
first is taja, which I suppose to be the result of a fungus which
attacks the undeveloped leaves and tender twigs. It is said by some
to be caused by careless picking, in which the twigs are broken. By
others it is said to result from the planting of seeds taken from
young plants. The only remedy is to remove and burn the diseased
portions. The second disease, if such it can be called, is the ravages
of a caterpillar called “ulo,” which makes its appearance in December,
and destroys the crop so quickly that it admits of no remedy.
“The method of picking and drying the Coca has been so often and so
well described of late that it is not necessary to dwell upon it.
Coca picking is a profession to which the children are trained from a
tender age. The leaves are picked singly, both hands being employed
with a rapid alternating motion, which strips a twig in an instant.
Great care is taken to avoid breaking the twigs, and the young leaves
are not picked. Little sacks are tied about the waist, or the women’s
aprons are pinned or sewn into the required form. They are then
transferred to larger sacks, which must be filled and emptied with
great promptness, or the leaves will become heated and turn black.
“The price here paid for picking is a Bolivian dollar, equal to about
seventy-one cents United States currency, or three shillings English,
for each thirty pounds, which, when dry, will weigh about twelve
pounds.
“The leaves are exposed to a hot sun upon a pavement of nicely-fitted
flat stones, and stirred occasionally until dry. Under the most
favourable conditions the drying is accomplished in about three
hours. About the Coca place are built the storage and packing sheds.
These are furnished with very broad doors, and men are in constant
attendance to sweep the Coca with brush-brooms through these broad
portals at the slightest indication of rain. A very few drops of rain
are sufficient to decolorise and ruin the sale of the Coca, though it
is my impression that such decolorisation, if produced by but little
rain, is no indication of loss of cocaine. During the first few days
that the dry Coca lies within the storage-sheds it undergoes a slight
sweating process.
“When I come now to speak of the best methods of packing the Coca
for export, it is fair to say that nothing definite is known. Such
Coca as has reached Europe or the United States in good condition has
done so purely by accident; for, perhaps, the very next lot, dried,
packed, and shipped as nearly as possible in the same manner, has
arrived entirely ruined. I have tried many methods, and as often as I
had thought that the secret was discovered, my hopes have resulted in
disappointment.
“As regards the exportation of the culture of Coca, the experiment
has been tried, I believe, but once. Several years since, Mr. F. L.
Steinart, of La Paz, shipped a small quantity of seeds _viâ_ London to
Ceylon, and during the past season the first products were shipped to
London and sold at a high price. Seeds for export should be exposed
for several days to a hot sun, so as to rapidly dry the fleshy
exterior, which thus forms a protection to the germ within.
“It is my opinion that the Coca-plant is adapted for culture in
many countries where it is now unknown. Among the countries where
it would be well to experiment with it are Guatemala, Mexico, the
East and West Indies, India, Southern China, portions of Africa, and
possibly of Italy. It is doubtful if it would grow in any portion of
the United States. Requiring an average temperature of at least 70°,
the only districts at all suited would be Florida and Southern Texas;
and it is highly probable that proximity to the sea-coast at so low
an altitude would prove fatal. Nor would irrigation prove adequate in
those countries possessing a long dry season. The plants must not only
have an abundant supply of water at the roots; they must be bathed in
a humid atmosphere for the greater portion of the year. But from what
I have read of some of the countries above named, I am confident that
the plant would there find a congenial home. Jamaica offers especially
hopeful conditions.”