See here: http://en.wikipedia....wiki/Avendesora
Avendesora is the last cutting remaining from the chora trees that lined the streets of Paaren Disen, in the Age of Legends. Chora trees are distinguished by their tri-foil leaves and the feeling of contentment a person gets when under one's branches. All chora trees except one were destroyed during the Breaking of the World.
Also here: http://wot.wikia.com/wiki/Chora
Chora trees are large, living, tree-like constructs with trefoil-shaped leaves, created during the Age of Legends. It is said that they emitted a sense of peace for any who passed below their branches. They were grown in abundant quantities in the cities of old, especially in V'saine and Paaran Disen. They are grown by the songs of the Ogier and Nym.[verify]