Epiphytic or velamen root: Some epiphytic orchids develop a special kind of aerial roots which hang freely in the air. These roots develop a spongy tissue called velamen which helps in the absorption of moisture from the surrounding air. eg. Vanda, Dendrobiutn, Aerides.
Foliar root: Roots are produced from the veins or lamina of the leaf for the formation of the new plant, eg. Bryophyllum, Begonia, Zamioculcas.
Sucking or Haustorial roots: These roots are found in parasitic plants. Parasites develop adventitious roots from the stem which penetrate into the tissue of the host plant and suck nutrients, eg. Ciiscuta (dodder), Cassytha, Orobanche (broomrape), Viscum (mistletoe), Dendrophthoe.
Photosynthetic or assimilatory roots: Roots of some climbing or epiphytic plants develop chlorophyll and turn green which help in photosynthesis, eg. Tinospora, Trapa natans (water chestnut), Taeniophyllum.
