When cast this spell created a 10 ft. thick ring of thorns surrounding the caster. This ring of thorns terminated at the height of the caster's chest and was open on top. Once cast the ring of thorns could not be moved by physical or magical means. The ring was immune to fire but could still be hacked apart by weapons.
The thorns of the ring were exceptionally sharp, causing a fair amount of physical harm to any creature attempting to pass through them to reach the caster. The thorns appeared to be even more harmful if a creature tried to aggressively force their way through them.