The grass in the picture are known as C4 plants. Unlike C3 and CAM plants, C4 plants live in high daytime temperatures and intense sunlight. The stomata of C4 plants are open during the entire day, and the CO2 they take up is turned into a 4 carbon compound first. Corn is a great example of a C4 plant. C4 plants are known to have a high water use efficiency, but cannot survive in cooler environments with little sunshine. Around 1% of all known plants are considered C4.