Branches of agriculture include aqua farming, farming, apiculture or beekeeping, fishing, forestry, ranching and whaling. Forestry is further divided into the four categories of agroforestry, analog forestry, forest gardening and forest farming. Agronomy is the science of producing plants for uses such as food, fuels, fiber and feed. Animal husbandry refers to raising and breeding livestock.
Agriculture is classified by the type of life produced or harvested, and it is thought of as sustainable or conventional. Conventional agriculture involves the use of modern technology to produce plants. These include inorganic fertilizers, pesticides and insecticides. It also requires altering the natural environment of land with techniques such as mono-cropping and eliminating diversity among crops.
Sustainable agriculture promotes maintaining the natural environment of the land using techniques that promote ecological principles. Polycropping, or planting a variety of crops, is commonly used. Different plants have different harvesting periods, the land is not left bare and the risk of soil erosion is reduced. The use of pesticides is either reduced or eliminated.
In the United States, conventional agriculture is the type of agriculture most used. Some crops are grown with a specific type of agriculture. Soybeans and wheat are more likely to be grown through conventional agriculture. Beets and squash are more likely to be grown using sustainable agriculture.