Cultivation of tobacco

Tobacco is cultivated similarly to other agricultural products. Seeds were at first quickly scattered onto the soil. However, young plants came under increasing attack from flea beetles (Epitrix cucumeris or Epitrix pubescens), which caused destruction of half the tobacco crops in United States in 1876. By 1890 successful experiments were conducted that placed the plant in a frame covered by thin cotton fabric. Today, tobacco is sown in cold frames or hotbeds, as their germination is activated by light.[citation needed] In the United States, tobacco is often fertilized with the mineral apatite, which partially starves the plant of nitrogen, to produce a more desired flavor. Apatite, however, contains radium, and lead 210—which are known carcinogens.[citation needed] After the plants are about eight inches tall, they are transplanted into the fields. Farmers used to have to wait for rainy weather to plant. A hole is created in the tilled earth with a tobacco peg, either a curved wooden tool or deer antler. After making two holes to the right and left - you would move forward two feet, select plants from your bag and repeat. Various mechanical tobacco planters like Bemis, New Idea Setter, and New Holland Transplanter were invented in the late 19th and 20th centuries to automate the process: making the hole, watering it, guiding the plant in — all in one motion.[citation needed] Tobacco is cultivated annually, and can be harvested in several ways. In the oldest method still used today, the entire plant is harvested at once by cutting off the stalk at the ground with a tobacco knife. It is then speared onto sticks, four to six plants a stick and hung in a curing barn. In the 19th century, bright tobacco began to be harvested by pulling individual leaves off the stalk as they ripened. The leaves ripen from the ground upwards, so a field of tobacco harvested in this manner will involve the serial harvest of a number of "primings," beginning with the volado leaves n

ar the ground, working to the seco leaves in the middle of the plant, and finishing with the potent ligero leaves at the top. Before this the crop needs to be topped when the pink flowers develop. Topping always refers to the removal of the tobacco flower before the leaves are systematically removed and, eventually, entirely harvested. As the industrial revolution took hold, harvesting wagons used to transport leaves were equipped with man-powered stringers, an apparatus that used twine to attach leaves to a pole. In modern times, large fields are harvested mechanically, although topping the flower and in some cases the plucking of immature leaves is still done by hand. Most tobacco in the U.S. is grown in Kentucky, Virginia and North Carolina. A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant. The formation of the seed completes the process of reproduction in seed plants (started with the development of flowers and pollination), with the embryo developed from the zygote and the seed coat from the integuments of the ovule. All seeds are different size, shape and colour. Seeds have been an important development in the reproduction and spread of flowering plants, relative to more primitive plants such as mosses, ferns and liverworts, which do not have seeds and use other means to propagate themselves. This can be seen by the success of seed plants (both gymnosperms and angiosperms) in dominating biological niches on land, from forests to grasslands both in hot and cold climates. The term "seed" also has a general meaning that antedates the above—anything that can be sown, e.g. "seed" potatoes, "seeds" of corn or sunflower "seeds". In the case of sunflower and corn "seeds", what is sown is the seed enclosed in a shell or husk, whereas the potato is a tuber.