186 1 ~ 1865 The American Civil War was a struggle between the capitalist system in the north and slavery in the south, and it was the second bourgeois revolution in American history. With the victory of the bourgeoisie, capitalism has been fully developed in all aspects of the United States. By the beginning of the 20th century, large-scale capitalist farms had occupied a major position in the United States, and agriculture had been capitalized. With the capitalization of agriculture, there have been two technological revolutions in agriculture. The basic feature of the first American agricultural revolution (from the end of 19 to the beginning of the 20th century) was that the backward tools of manpower and animal power were replaced by horse-drawn agricultural machines. Modern natural science began to be used in agriculture, such as the use of chemical fertilizers and pesticides, the improvement of crops and livestock varieties, and the emergence of irrigated agriculture. In addition, the specialization of agricultural production and regional division of labor have also been formed. The second agricultural revolution in the United States (1920s-40s) was marked by the basic mechanization of agriculture and the technological reform and development of hybrid corn.

After the civil war broke out in 186 1, the federal government promulgated the Homestead Law in 1862 to win the support of the masses against the war of slave owners in the south. According to the Homestead Law, any American citizen who has not participated in the anti-federal rebellion and is headed by 265,438+0 years old, or who has applied for naturalization but has not resisted the United States with a gun, can apply for 65,438+0/4 square miles (65,438+0 Indian acres) of undistributed public land. After five years of cultivation, the land will become unpaid. It is also stipulated that if you apply for a homestead, you can get it per mu after registration for half a year! Pay $25 for the house. The Homestead Law provided free land for the settlers who moved in, stimulated people to cross the Mississippi River and develop the west, opened up a vast world for the small yeoman economy to be generally established in the west, and promoted the development of agricultural productivity. Immigrants coming one after another brought new varieties of crops and livestock and advanced agricultural technology. The United States began to carry out large-scale agricultural production, and the reclamation of the west promoted the great development of American agriculture. /kloc-agricultural mechanization developed rapidly in the second half of the 0/9th century. From 1860- 19 16, the cultivated land area has increased from 407 million mu to 879 million mu, the improved land area has more than tripled, and the output of wheat and corn has increased by about 3 times. Large-scale production in agriculture has crowded out and merged small-scale production. In the north, which is dominated by industry, intensive agriculture is increasingly used in agriculture. In other areas, the number of large farms has gradually increased. 1900, half of the total agricultural products in the United States were produced by 1/6 big farmers. American agriculture has realized planting specialization to a great extent and formed some famous production belts, such as corn belt, wheat belt and cotton belt. This regional division of labor enables all regions in the United States to give full play to their comparative advantages, which is conducive to reducing costs and improving productivity. /kloc-In the first half of the 20th century, due to the rapid development of agricultural production, the United States invented and adopted a series of new agricultural machinery to improve labor productivity. Animal-drawn machinery has been used since the beginning of 19 century, and field cultivators, seeders, lawn mowers, harvesters and threshers have come out one after another. Since 1930s, iron plows have been widely used instead of wooden plows. By the 1950s, horse-drawn farm tools had been widely used. 1850, the United States began to use steam engines. At the beginning of the 20th century, the internal combustion engine developed rapidly. 19 10, the United States began to implement agricultural mechanization and became the earliest country in the world.