Tobacco Botany
Tobacco is a member of the Solanaceae (nightshade) family, which also includes many crop species such as tomatoes, potatoes and peppers. Nicotiana tabacum is the principal species producing commercial tobacco. Some commercial tobacco is also obtained from a sister species, Nicotiana rustica, which is a smaller plant with fewer leaves than N. tabacum. There are more than 70 species of tobacco, of which 45 are native to the Americas. The two cultivated species, common tobacco and wild tobacco, are annuals-they live only one growing season. Common tobacco is 1 to 3 m (3 to 10 ft) tall and has a thick, woody stem with few side branches. One plant typically produces 10 to 20 broad harvestable leaves that branch alternately from the central stalk. The leaf size depends on the strain. The narrow, trumpet-shaped flowers are dark pink to almost white. Wild tobacco is about 0.6 m (2 ft) tall and has a stem that is more slender and less woody than common tobacco. The leaves have a short stalk that attaches to the stem. The flowers are pale yellow with five separate lobes.

Tobacco History
2,000 years ago, natives of the Americas used tobacco as a medicine, as a hallucinogen in religious ceremonies, and as offerings to the spirits they worshiped. When Italian Spanish explorer Christopher Columbus traveled to the Americas in 1492, he observed the Arawak people of the Caribbean smoking tobacco loosely rolled in a large tobacco leaf. They also smoked tobacco through a tube they called a tobago, from which the name tobacco originated. Columbus's crew introduced tobacco growing and use to Spain. During the next 50 years, sailors, explorers, and diplomats helped spread pipe and cigar smoking throughout Europe. At first, it was used medicinally as a purported treatment for diseases and disorders such as bubonic plague, migraines, labor pains, asthma, and cancer. Within 100 years, however, smoking for pleasure became common. In 1612 the British colony at Jamestown, Virginia, began growing wild tobacco and exporting it to England.

They soon switched to common tobacco, the milder kind grown in the West Indies and in demand in Europe. It quickly became the main crop grown in the colonies and was so profitable that without it, historians agree, the English colonies in North America would have failed. As tobacco farming expanded through the colonies, growers brought British prisoners and debtors to work the fields. These indentured servants earned their freedom after 5 to 12 years of labor. Growers soon found it more profitable to bring in African slaves, since they never had to be given their freedom. Slavery enabled growers to farm larger areas, making giant plantations possible. After 1776 tobacco farming expanded from Virginia south to North Carolina and west as far as Missouri. In about 1864 an Ohio farmer happened upon a chlorophyll-deficient strain of tobacco called white burley, which became a main ingredient of American blended tobaccos. Cigarettes were invented in 1614 by beggars in Seville, Spain, a center for cigar production. The beggars collected scrap tobacco and rolled it in paper.

Main Types of Tobacco
Four main types are identified according to the method of curing (drying): Flue-cured - also known as "flue-cured Virginia", or just "Virginia", after the US State where this method of curing using artificial heat was first propounded, and "Bright" because of its lustre and colour. Air-cured - which includes burley, cigar and light and dark air-cured tobaccos. It is cured in ambient air with minimal artificial control of humidity. Fire-cured - this type is cured by a similar process to flue-cured, except that heat is supplied by open smouldering fires to give the product its characteristic smoked aroma and flavor. Sun-cured - oriental tobaccos belong to this type. Their strong flavor and taste is developed in the first phase of curing and then retained by drying leaves outside in the sun. To achieve their individual characteristics, each type also needs to be grown in the right soils and climate, be managed correctly and cured according to its specific method. This is illustrated by the following comparisons between flue-cured Virginia, burley and oriental, the main types used in cigarette manufacture.

Tobacco Production
As the world's leading non-food crop, tobacco is chosen by farmers from over 100 countries for its performance under widely varying climatic and soil conditions to meet the demands of many different markets.
Tobacco grows both in tropical and temperate regions, and it can be grown as far north as Canada and Norway. It thrives best in areas with a frost-free growing season of 120 to 170 days, depending on the type of tobacco. Good quality tobacco requires fertile, well-drained, moist soil and warm temperatures. Most types of tobacco are grown in full sun. Environmental factors influence the plant's characteristics. Soil, for example, can affect leaf size, texture, and color. Sandy soils tend to produce a relatively large leaf that is light in color and body, fine in texture, and burns with a weak aroma. Heavier soils, which contain silt and clay, tend to produce a small, dark leaf with a heavy body and a strong aroma when burned.
Several strains of common tobacco are grown for use primarily in different tobacco products. Virginia tobacco is the main tobacco used in cigarettes; most of it is grown in North Carolina, Georgia, and Virginia. Burley tobacco is used in cigarettes and pipes. Several countries, including the United States, Turkey, and Cuba, grow cigar tobacco.
Tobacco plants are susceptible to attack from a wide range of insects and bacterial, fungal, and viral diseases. To counteract these problems, tobacco farmers grow strains of tobacco that resist diseases and insects. By rotating crops (planting tobacco one year and a different crop in the same field the next year), farmers keep the population of tobacco pests in check by depriving them of tobacco plants on alternate years. Before planting, farmers may work a fungicide into the soil to control fungal diseases, such as blue mold and damping-off. They may also fumigate the soil to control nematodes-microscopic worms that infest the roots. Growers also use herbicides to control weeds and insecticides to control insects.

The annual tobacco cultivation cycle begins with the planting of seeds. Tobacco seeds are extremely small: one million seeds (the potential yield of a single mature plant) weigh about 80 g (about 3 oz). Tobacco seeds are so tiny that they need special care to keep them from drying out once they begin sprouting. To keep young plants watered and weeded, growers sow the seeds in specially prepared seedbeds of fertile, loose soil, rather than directly in the field.
One to two months after planting, the growers transplant the seedlings into the field-a labor-intensive process called setting the tobacco. As flowers form on the plants, growers remove them in a process called topping, which encourages more leaf growth. Tobacco is harvested 70 to 130 days after setting. The harvesting method used depends on the type of tobacco. For some tobaccos, farmers cut whole plants off at the ground and spear them onto a stick about 1 m (3 ft) long, called a tobacco stick. Each stick holds about six plants. For other tobaccos, farmers remove the mature leaves and string them on wires, leaving the rest of the plant to continue growing.Tobacco production is highly labour intensive and is similar to many aspects of horticulture. The tiny seed is planted in specially prepared soil and raised as a seedling before being transplanted, mostly by hand, into the growing fields.

Once harvested, the tobacco leaf is taken for curing by heat, air or wood smoke. The aims are to remove the moisture and vegetable taste of the green leaf and to prepare it for packing and eventual processing.
Most tobaccos (62 per cent in 1993) are flue cured using heat from energy sources such as coal (67.1 per cent), oil and gas (17.2 per cent) and wood (15.7 per cent). These energy sources heat air which is circulated through the racks of tobacco leaf, either by convection or using fans for better control.
Air-cured tobacco is sheltered from wind and sun in a well-ventilated barn, where it air dries for six to eight weeks. Air-cured tobacco is low in sugar, which gives the tobacco smoke a light, sweet flavor, and high in nicotine. Cigar and burley tobaccos are air cured.
In fire curing, smoke from a low-burning fire on the barn floor permeates the leaves. This gives the leaves a distinctive smoky aroma and flavor. Fire curing takes three to ten weeks and produces a tobacco low in sugar and high in nicotine. Pipe tobacco, chewing tobacco, and snuff are fire cured.

Tobacco products include cigarettes, cigars, and pipe tobacco, which are smoked; snuff, which is inhaled into the nose; and chewing tobacco, which is chewed but not swallowed. Tobacco is also used for nicotine products, such as insecticides and medicines to help people quit smoking. The nitrogen-rich stalks left after harvesting are used as a fertilizer in tobacco-growing regions.
In the first stages of processing, the stems and veins are removed and the leaves are cut into strips. Various tobacco strains are then blended in rotating drums. For example, blends of bright, burley, and oriental tobaccos are used in cigarettes. Moisture-holding substances, such as apple juice or glycerin, and flavorings, such as honey, licorice, or mint, are sometimes added to the blends. The blended tobaccos are then chopped into small shreds.

General Info On Tobacco Industry
Approximately 7 million tons of commercial tobacco are grown each year, with a value of $39 billion. Leading tobacco-growing countries are China, the United States, India, Brazil, Turkey, and Zimbabwe. Tobacco is an economically important crop for many nations-about 2 million tons of unmanufactured tobacco leaf, at a value of about $6,500 per ton, are exported each year worldwide. Brazil leads in exports, with about 15 percent of the total, followed closely by the United States, with about 11 percent of the total. As smoking has become less popular in the United States and Europe, cigarette manufacturers have found new markets in eastern Europe, Asia, Africa, and the former Soviet Union. Due to the aggressive marketing efforts of the international tobacco industry, tobacco consumption in these areas is expected to rise by almost 3 percent annually.

Flue-cured Virginia