The Azure Front is located south east of the Violet Stand in southern Crystalsong Forest. Artifacts belonging to the blue dragonflight can be seen in the area. It is the front lines between the blue dragonflight and Dalaran.
The blue dragonflight seems to be drawing power from the largest crystal tree with a chain of three surge needles. As there is a fourth surge needle with a different crystal on it between the needle at the end of the channeling and the dome of the Violet Stand, they may be attempting to use the energies from a tree as a weapon.