Poaceae Poaceae Poaceae () 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. 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 , following the Asteraceae, Orchidaceae, Fabaceae and Rubiaceae. Grasslands such as savannah and prairie where grasses
Lists of organisms by population 400 billion trees on our globe. However, more recently, in 2015, using better methods, the global tree count has been estimated at about 3 trillion. Other studies show that the Amazonian forest alone yields approximately 430 billion trees. Extrapolations from data compiled over a period of 10 years suggest that greater Amazonia, which includes the Amazon Basin and the Guiana Shield, harbors around 390 billion individual trees. Lists of organisms by population This is a collection of lists of organisms by their population. While most of the numbers are estimates, they have been made by the experts in their fields.