Grains are small, hard, dry seeds, with or without attached hulls or fruit layers, harvested for human or animal consumption. Agronomists also call the plants producing such seeds "grain crops". The two main types of commercial grain crops are cereals such as wheat and rye, and legumes such as beans and soybeans.
After being harvested, dry grains are more durable than other staple foods such as starchy fruits (plantains, breadfruit, etc.) and tubers (sweet potatoes, cassava, etc.). This durability has made grains well suited to industrial agriculture, since they can be mechanically harvested, transported by rail or ship, stored for long periods in silos, and milled for flour or pressed for oil. Thus, major global commodity markets exist for canola, maize, rice, soybeans, wheat, and other grains but not for tubers, vegetables, or other crops.
Grains and cereals
In botany, grains and cereals are synonymous with caryopses, the fruits of the grass family. In agronomy and commerce, seeds or fruits from other plant families are called grains if they resemble caryopses. For example, amaranth is sold as "grain amaranth", and amaranth products may be described as "whole grains". The pre-Hispanic civilizations of the Andes had grain-based food systems but, at the higher elevations, none of the grains was a cereal. All three grains native to the Andes are broad-leafed plants rather than grasses such as corn, rice, and wheat.
Warm-season (C4) cereals
- finger millet
- foxtail millet
- Kodo millet
- Japanese millet
- Job's Tears
- maize (corn)
- pearl millet
- proso millet
Cool-season (C3) cereals
Starchy grains from broadleaf (dicot) plant families:
- amaranth (Amaranth family)
- buckwheat (Smartweed family)
- quinoa (Amaranth family, formerly classified as Goosefoot family)
Grain legumes or pulses
Members of the pea family. Pulses have higher protein than most other plant foods. They may also contain starch or oil.
- common beans
- common peas (garden peas)
- fava beans
- lima beans
- mung beans
- pigeon peas
- runner beans
Grains grown primarily for the extraction of their edible oil. Vegetable oils provide dietary energy and some essential fatty acids. They can be used as fuel or lubricants.
Historical impact of grain agriculture
Because grains are small, hard and dry, they can be stored, measured, and transported more readily than can other kinds of food crops such as fresh fruits, roots and tubers. The development of grain agriculture allowed excess food to be produced and stored easily which could have led to the creation of the first permanent settlements and the division of society into classes.
- Babcock, P. G., ed. 1976. Webster's Third New International Dictionary. Springfield, Massachusetts: G. & C. Merriam Co.
- "Lost Crops of the Incas: Little-Known Plants of the Andes with Promise for Worldwide Cultivation". Office of International Affairs, National Academies. Washington D.C.: National Academy Press. 1989. p. 24.
- Vaughan, J. G., C. Geissler, B. Nicholson, E. Dowle, and E. Rice. 1997. The New Oxford Book of Food Plants. Oxford University Press.
- Wessel, T. 1984. "The Agricultural Foundations of Civilization". Journal of Agriculture and Human Values 1:9–12