<Li> Aerial roots: roots entirely above the ground, such as in ivy (Hedera) or in epiphytic orchids . Many aerial roots, are used to receive water and nutrient intake directly from the air - from fogs, dew or humidity in the air . Some rely on leaf systems to gather rain or humidity and even store it in scales or pockets . Other aerial roots, such as mangrove aerial roots, are used for aeration and not for water absorption . Other aerial roots are used mainly for structure, functioning as prop roots, as in maize or anchor roots or as the trunk in strangler fig . In some Epiphytes - plants living above the surface on other plants, aerial roots serve for reaching to water sources or reaching the surface, and then functioning as regular surface roots . </Li> <Li> Contractile roots: these pull bulbs or corms of monocots, such as hyacinth and lily, and some taproots, such as dandelion, deeper in the soil through expanding radially and contracting longitudinally . They have a wrinkled surface . </Li> <Li> Coarse roots: roots that have undergone secondary thickening and have a woody structure . These roots have some ability to absorb water and nutrients, but their main function is transport and to provide a structure to connect the smaller diameter, fine roots to the rest of the plant . </Li> <Li> Dimorphic root systems: roots with two distinctive forms for two separate functions </Li>

The primary function of the root is to