Orchid Roots
The roots of epiphytic and climbing orchids are one of their most striking characteristics. The roots are roughly of the same diameter throughout their length, and there is no tap root. The exposed roots are covered in a silvery gray coat called velamen, which darken with age. The velamen is a spongy and absorbent layers of dead cells. The root tip is rather green and can photosynthesize. The root will attach to any suitable surface, such as a branch, and cannot be pulled away without damaging it. When the roots are no longer exposed, they become pale and swollen and are easily rot if they get water-logged. Roots are important to epiphytic orchids, as these orchids grow high above ground and need a good support. The roots can travel a few meters along the branch. There are several orchid species which are depending on their green roots to produce their food, as they are leafless. Their stems are merely stumps to hold the flowers. Terrestrial and lithophytic orchids usually have hairy roots, and are more tolerant of damp conditions, but they still need good drainage.  Roots of Phalaenopsis Author: Mohd Yazid Husain (Creative Commons Attribution-Share Alike 2.0 Generic) | ||
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