gramineae

Gramineae, commonly known as the grass family, is a large and widely distributed group of monocotyledonous flowering plants. It is typically treated as Poaceae in modern classifications and comprises about 780 genera and around 12,000 species, occurring in nearly all regions of the world. Grasses range from tiny annuals to vast bamboos and include many of the cereals that underpin human agriculture.

Most graminaceous plants are herbaceous, though some subfamilies include woody forms such as bamboos. They usually have hollow, jointed stems (culms), sheathing leaves with a ligule at the leaf base, and parallel-veined blades. The inflorescence is often a spikelet, arranged in spikes, racemes, or panicles. Each spikelet generally bears one or more florets with highly reduced floral parts. Flowers are typically small and wind-pollinated, and the fruit is a caryopsis, in which a thin fruit wall adheres to the seed.

Ecologically, grasses are foundational in many ecosystems, from savannas and prairies to wetlands and alpine zones. They exhibit great adaptability to disturbance and a range of climates, with many C3 and C4 photosynthetic types. Grasses frequently reproduce by seeds and also spread vegetatively via rhizomes or stolons. They are important for soil stabilization and as forage and habitat for numerous organisms.

Economically, the family is of immense significance. Major cereals—rice, wheat, maize, barley, oats, sorghum, and millet—are grasses and provide a large portion of human calories. Forage grasses support livestock production, turf grasses sustain lawns and sports fields, and many species are used ornamentally or for bamboo and other industrial materials. Taxonomically, Poaceae is divided into several subfamilies, including Pooideae, Panicoideae, Ehrhartoideae, and Bambusoideae.