Grasses are, in human terms, perhaps the most economically important plant family. Grasses' economic importance stems from several areas, including food production, industry, and lawns.
Food production
Agricultural grasses grown for their edible seeds are called cereals. Three cereals – rice, wheat, and maize (corn) – provide more than half of all calories eaten by humans. Of all crops, 70% are grasses. Cereals constitute the major source of carbohydrate for humans and perhaps the major source of protein, and include rice in southern and eastern Asia, maize in Central and South America, and wheat and barley in Europe, northern Asia and the Americas.
Sugarcane is the major source of sugar production. Many other grasses are grown for forage and fodder for animal food, particularly for sheep and cattle. Some other grasses are of major importance for foliage production, thereby indirectly providing more human calories.
Industry
Grasses are used for construction. Scaffolding made from bamboo is able to withstand typhoon force winds that would break steel scaffolding. Larger bamboos and Arundo donax have stout culms that can be used in a manner similar to timber, and grass roots stabilize the sod of sod houses. Arundo is used to make reeds for woodwind instruments, and bamboo is used for innumerable implements.
Grass fibre can be used for making paper, and for biofuel production.
Phragmites australis (common reed) is important in water treatment, wetland habitat preservation and land reclamation in the Old World.
Lawn and ornamental grasses
Grasses are the primary plant used in lawns, which themselves derive from grazed grasslands in Europe. They are also provide an important means of erosion control (e.g., along roadsides), especially on sloping land.
Although supplanted by artificial turf in some games, grasses are still an important covering of playing surfaces in many sports, including football, tennis, golf, cricket, and softball/baseball.
Ornamental grasses, such as perennial bunch grasses, are used in many styles of garden design for their foliage, inflorescences, seed heads, and slope stabilization. They are often used in natural landscaping, xeriscaping, contemporary or modern landscaping, wildlife gardening, and native plant gardening.