Poaceae
List of Poaceae genera
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The true
grasses are
monocot (class
Liliopsida)
plants of the
family Poaceae (formerly
Graminae). There are some 600 genera and perhaps 10,000 species of grasses. It is estimated grasslands comprise 20% of the vegetation cover of the earth. This family is the most important of all plant families to human economies, including lawn and forage grasses, the staple
food grains grown around the world, and
bamboo, widely used for construction throughout
Asia.
Grasses generally have the following characteristics:
- Typically hollow stems (called culms), plugged at intervals (the nodes).
- Leaves, arising at nodes, alternate, distichous (in one plane) or rarely spiral, and parallel-veined.
- Leaves differentiated into a lower sheath hugging the stem for a distance and a blade with margin usually entire; a ligule (a membranous appendage or ring of hairs) lies at the junction between sheath and blade.
- Flowers small (called florets), lacking petals, and grouped into spikelets arranged in a panicle, raceme, spike, or head; the flowers wind-pollinated.
- Fruit a caryopsis (also called a grain).
Agricultural grasses grown for food production are called
cereals.
Cereals constitute the major source of calories for humans, and include
rice in
India and the
Far East,
maize in
Mexico, and
wheat and
barley in
Europe and
North America. Staple food grains are often called
corn.
Some commonly known grass plants are:
