Grasses are found globally and comprise one of the three largest plant groups. The other two groups include the composite flowers (having multiple flowers) such as the asters and, the orchids. That's right, the orchids of all groups. Sometimes as many as several hundred different species can be found in one hectare (2.5 acres) in the tropics. Grasses are monocots with only one cotyledon in the seed head. The grasses are generally broken down into warm season grasses such as Big Blue Stem, Little Bluestem, Indian Grass, and Switch Grass. These have a C4 metabolism which means they grow the best in heat. The cool season grasses such as Bottlebrush Grass and Sweet Grass grow the best in the spring and the fall.