Holly

 Associated by Druidic tradition to the grand majesty of the Unicorn. Holly is one of the most fiery of woods and second only to Oak for its sacred regard by the Druids. The Gaelic “tinne” is thought to mean “fire.”  Holly has been regarded as a powerful protective wood, good against evil spirits, poisons, angry elementals, and lightning.

Holly
(Ilex opaca)
Purity, strength, logic, protection, power transfer,
blocking unwanted forces and healing.
Holly is the whitest wood in the world and is often 
associated with purity and the unicorn.
Natural Habitat – South Eastern United States
Wood Hardness – 950

sources:
http://www.macfies.com/wood-properties.html
http://www.bardwood.com/woods.htm