Poales

Poales is a taxonomic order of flowering plants in the monocotyledons. The order includes families of plants such as the grasses, bromeliads, and sedges.
The earliest fossils of Poales date to the late Cretaceous period, about million years ago. Some suggest the origin of the group may be 115 million years ago in South America. The earliest known fossils include pollen and fruits.
The flowers are typically small, enclosed by bracts, and arranged in inflorescences (except in the genus "Mayaca", with solitary terminal flowers). The flowers of most species are wind pollinated. The seeds usually contain starch.
Among monocots, the Poales come second to the orchids in number of species. But in economic terms, they are far more important. In fact, the true grasses (Poaceae) produce by far the most important grains eaten by humans and other animals.
One recent classification lists these families: 
Diversity and uses.
The Poales are the most economically important order of monocots and possibly the most important order of plants in general. Within the order, by far the most important family economically is the family of grasses (Poaceae, syn. Gramineae), which includes barley, maize, millet, rice, and wheat. It is also the largest family in the order, far outnumbering the other families: