棉花是世界上主要农作物之一,人类用棉纤维织布的历史已有3000多年,有些国家和地区还用棉籽油做菜,也有不少农民用棉籽饼喂养牲口。全世界共有40多个国家在种植棉花,虽然有些地方是任凭棉花野生野长,但大部分地区则和种植其它农作物一样,全靠人工种植。早春播种,仲夏施肥,秋天采棉,前后约需170天时间,且必须气候温暖,雨水适量,阳光充足。在美国,若在40年前,棉花产量每公顷能有280公斤, Cotton is one of the main crops in the world. The cotton weaving has been used by mankind for more than 3,000 years. Some countries and regions use cottonseed oil for cooking. Many farmers use cottonseed cake to feed their animals. More than 40 countries around the world are growing cotton. Although in some areas the cotton is wild, most of the area, like other crops, is grown entirely by hand. Sowing in early spring, fertilizer in midsummer, picking cotton in autumn, it takes about 170 days before and after, and the climate must be warm, the amount of rainfall is adequate and the sunshine is abundant. In the United States, if 40 years ago cotton output per hectare could have 280 kilograms,