"Poaceae (/poʊˈeɪsiaɪ/) or Gramineae is a large and nearly ubiquitous family of monocotyledonous flowering plants known as grasses, commonly referred to collectively as grass. Poaceae includes the cereal grasses, bamboos and the grasses of natural grassland and cultivated lawns and pasture.
The Poaceae are the most important source the world´s dietary energy supply. They provide, through direct human consumption, just over one-half (51%) of all dietary energy; rice provides 20%, wheat supplies 20%, maize (corn) 5.5%, and others grains 6%.
Grasses have stems that are hollow except at the nodes and narrow alternate leaves borne in two ranks. The lower part of each leaf encloses the stem, forming a leaf-sheath. With around 780 genera and around 12,000 species, Poaceae are the fifth-largest plant family, following the Asteraceae, Orchidaceae, Fabaceae and Rubiaceae." - (en.wikipedia.org 03.10.2019)
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