Celtic Reiki is a variation of Usui Reiki which uses vibrations of the Earth and specific trees and shrubs in order to create an environment suitable for healing and manifestation.
The Reiki energy mimics the frequency of various plants and trees so as to work in
accordance with channeled and Celtic wisdom.
As Celtic Reiki is an Earth-energy Reiki, it is channeled up through the Base chakra, rather than down through the Crown (which is the case in Usui Reiki).
This makes it similar in some ways to Kundalini Reiki, although Celtic Reiki does not act on the Kundalini. Instead, it produces results akin to traditional Usui Reiki, although these are influenced considerably by the energy techniques of the Celts