CHAPTER II

THE CULTIVATION OF THE TOBACCO PLANT

CLIMATIC AND SOIL CONDITIONS. TREATMENT OF THE GROWING PLANT. SHADE GROWN TOBACCO. HARVESTING.

THE CULTIVATION OF THE TOBACCO PLANT

A few general facts concerning the culture of the tobacco plant and its treatment until it reaches the hands of the manufacturers will be of interest for the smoker.

The general principles underlying the culture of tobacco are the same whether it is intended for the cigar, pipe smoking or cigarette trade; but the treatment of the leaf after it is harvested differs considerably.

Tobacco is a perennial plant. It is, however, usually raised each year from seed. The seedlings are usually ready for planting towards the end of May and are generally planted between the last week in May and the middle of June.

The successful raising of tobacco depends on four principal factors: (1) the climate, (2) the nature of the soil, (3) the seed, and (4) on the method of culture.

The _climate_ must be such as to favor rapid growth and therefore must furnish sufficient heat and moisture during the time the plant is growing. The fineness of the texture and the elasticity of the leaf depend on the climate.

On the _soil_ the plant depends for its food, and for the absorption of those chemical constituents on which depend the burning qualities, the strength and the color.

The physical qualities of the plant, structure and form, thickness of veins, size, shape and distribution of leaves, are derived from the _seed_.

Finally, on the _method of cultivation_ (including the curing process) depends in part the final color, flavor and aroma; the type and trade value; that is to say, on successful culture and harvesting and treatment at the right time and in the best way, must depend the grower's hopes of the final value of his crop. The quantity of nicotine, essential oils, etc., on which flavor and strength depend, is regulated to the greatest extent by the time of cutting.

The nature of the soil is a very important matter in the culture of tobacco, for the color of the cured tobacco leaf depends almost entirely on the soil. The light colored leaf is grown on light colored soil and the darker leaf is grown on heavy, dark soil. The best type of soil for the raising of tobacco intended for the cigar trade is a warm, deep, sandy loam which rests on permeable well-drained subsoil. The very light colored yellow tobacco cannot be raised except on light colored, porous soils; and so susceptible is this matter of the coloring of the leaf that it has been noted that the darkening of the soil by a liberal allowance of stable manure will, on a very light colored soil, change the color of the tobacco leaf from a bright yellow to a mahogany shade. Very light sandy soils or very light loams with clayey subsoils are usually chosen for these light yellow tobaccos. Although by processes subsequent to growth it is possible to darken the color of tobacco leaf, there is no known process that will make a dark leaf light in color.

Moreover, the soil must be very fertile and rich in the special substances needed by the growing plant. This is all the more necessary because tobacco is a rapidly growing plant, and reaches its maturity within a few months after its planting. The rapidity of growth therefore demands a rich fertile soil well stored with plant food. Good manuring, or liberal treatment with fertilizers, is essential for keeping such soils in prime condition, because the period of growing must not be extended.

Tobacco is usually planted in rows, the rows being from three to four feet apart, the usual arrangement being that the plants are generally about 12 or 18 inches apart in the row. Some planters, however, give the plants more room for many reasons, varying the distance between the plants even as much as 30 inches. Cigar leaf tobacco plants are usually placed about 14 inches apart.

There are various operations necessary during the growth of the plant. The most important of these for our purpose are those known as "priming" or "thinning out" and "cutting." Priming is usually done when the plant is well advanced in growth, but the time varies with different growers and according to the species. It consists in removing the lower or imperfect leaves from the plant, or these which have in any way become injured from insect or other harmful agencies. As a general rule the larger the number of leaves there is on a plant the lower is the quality of the subsequently cured leaf. An average of about 10 leaves to each plant is what is favored by most growers, and the plants are usually thinned to this extent. Seed buds are removed also at the same time and for the same reason. If the plants are "thinned" late and when they are approaching full growth the leaves removed are not destroyed, but are cured separately and sold as inferior quality and are usually called "primings" or "planters lugs."

In the Southern American States the time allowed for the growth and maturing of the plant is somewhat longer than in the eastern and more northerly states where the soil, owing to richer fertilization, favors the rapid growth. Moreover, a stronger quality of tobacco is wanted and the extra time allows the plant to effect a greater elaboration in its cells of the oils and gums, etc., which contribute particularly to strength and flavor.

SHADE GROWN TOBACCO

The matter of rapid growth has, however, its limitations. Too much sunlight is considered a disadvantage. Under such powerful action, nutrition is drawn quickly from the soil and the plants ripen too quickly. Under such circumstances the leaves tend to become heavy bodied and not very large in size. To defeat this tendency and produce large, thin silky leaves for the cigar trade, the grower sometimes covers his field with a tent of cheese-cloth or similar protection from the glare of the sun. The ripening process is thereby slowed and the leaves are thinner, larger and lighter in shade. This method is employed principally in Cuba, Florida and Connecticut where cigar wrapper leaves are produced, and such tobacco is known as shade-grown.

Tobacco which has been planted out at the end of May or early in June is usually ready for harvesting at the end of August or beginning to middle of September. The actual time of harvesting varies a good deal according to the variety grown and the physical condition concerned in the growing of the plant. The heavier tobaccos which are intended for the export trade are usually harvested late. The most important operations connected with the culture of the tobacco leaf are the "yellowing" and "curing" processes, and, as these commence with the cutting of the plant, this latter must be done under strictly favorable conditions in order to insure proper results. The cutting must not be done while the sun is very hot, or while there is rain, or before the plant is fully matured. On the other hand, after the plant has reached its maturity, it must not be allowed to continue its growth, which along with other things would be likely to increase its nicotine content which is not desirable. The experienced tobacco grower knows well from the appearance of the plant when it is best fitted for cutting. The leaves become thick and heavy and assume a drooping appearance. They become crisp with a tendency to break easily, and a mottled, spotty look is noticeable on them. The surface becomes gummy and oily; the oily substances increases and exudates as the days pass. When these signs appear the tobacco is cut on the first day when the weather favors. It is usual in most cases to split the stalks down the middle and allow the leaves to wilt, before the stalk is entirely cut through. After sufficient wilting the leaves are gathered in piles and exposed to the action of the sunlight; or they are stuck by the stalks on poles or framework and so exposed that the sun and air have free access to all parts. This is the best and most approved practice. "Yellowing" of the leaf is very rapid after the plant is cut; it is the natural effect due to cutting off the food supply of the leaf and the consequent slow death of the vitality of the cells. It must be remembered that the leaves are large, varying in size (according to species) from 12 inches to over 2 feet in length. Such a leaf needs a large quantity of food and the sudden cutting off of the supply effects a rapid change in appearance. The leaves are allowed to hang on the scaffolds 3 to 5 days until they are fully yellowed. They are then ready for the process of "curing," which is the most important operation connected with cultivation. The "curing" and "fermentation" which the leaf undergoes are chemical actions and their success depends on the proper method of "yellowing." The leaves must not be exposed to the sun too long, because the cells would lose their vitality too rapidly and be unfitted for the new part they have to play in the curing process. The chemical changes will be explained in subsequent chapters. It is desired that the reader should understand that to ensure a successful final issue the planter has need to watch continuously and to know all the conditions. If the leaf does not "yellow" properly no amount of after care in curing will make up for this deficiency. In tobacco growing as in everything else, to ensure final high quality each step in the process must be executed with skill, care, and judgment.

The yield of tobacco per acre varies from about 300 lbs. of leaf in the southern states to 1,000 lbs. or more in the eastern. 700 to 800 lbs. per acre is considered a good average crop.

REFERENCES

KILLEBREW AND MYRICK. _Tobacco leaf; its culture and cure, marketing and manufacturing._ Part I. New York, 1897.

BILLINGS, E. R. _Tobacco; its history, varieties, culture, etc._ Chapter XIII. Hartford, Conn., 1875.

LAURENT, L. _Le tabac; sa culture et sa préparation production et consummation dans les divers pays._ Paris, 1900.

U. S. DEPT. OF AGRICULTURE. Farmers' Bulletins Nos. 6 and 60. _Tobacco._

U. S. DEPT. OF AGRICULTURE. Bureau of Plant Industry. Bulletin 96. _Tobacco breeding._