Differences can also be seen in the root systems where plants adapted to arid, dry, environments have root systems that are frequently shallow and very wide spread. This allows them to catch as much of the limited rainfall as possible before it moves down into the ground. Some of these plants are also capable of producing chemicals that flow out into the soil and prevent other plants from growing near them. This reduces competition and increases the amount of rain they can catch. In terms of traits that are easily studied, one of the most important adaptations that some plants have made to life on land, and particularly to living in dry areas, is by modifying their leaves.
Leaves are one of the most adaptable parts of the plant.
It is not unusual for one plant to have several types of leaves with shade leaves, sun leaves, young leaves, and mature leaves all present. Leaves are responsible for the process of photosynthesis and are thus the area where the most water and gas exchange occurs. This occurs through the stomata, the microscopic openings in the epidermis. Therefore, the more stomata a plant has, the more that are present on the top of the leaf and the more exposed they are, the more water will be lost. Thus, a plant may have adaptations that would reduce the number of stomata, move more of them to the bottom of the leaf or lower the stomata under the epidermis.