Simple tutorial on the use of Wild Growth.
Wild Growth (WG) is the druid restoration 51-talent-point spell. It is an AoE heal that you cast on another person: it does not automatically center on yourself, like Tranquility does. Also unlike Tranquility, Wild Growth can be cast on other raid members (as well as mobs and bosses, in fact!), rather than only your party. It has a 6-second cooldown and a 7-second duration, with a total of 7 ticks of healing applied during that time. The ticks occur quickly at first, and then slow down towards the end of the spell duration.
Because it can be cast upon other raid members or enemies and its area of effect is centered upon your target rather than yourself, Wild Growth requires a bit of finesse to use effectively; if you miscast the spell, its cooldown will prevent you from having another chance for 6 seconds, and in the healing world, that could mean deaths.
Here is the diagram style I will be using to illustrate WG. The little colored circles are people, and the big blueish circle is your Wild Growth's area of effect. It has a 15-yard radius centered on the person (or pet or enemy) you cast the WG on; the whole circle is 30 yards in diameter. Yay geometry!
If you cast WG on yourself, only those people within 15 yards of you will receive the HoT: yourself included. Everyone else is left out and is sad. Or angry. Maybe that's why I made them red.
If you cast the spell on someone else (you have a 40-yard range to target with), then they, and everyone else within 15 yards of them, is eligible for the spell (assuming they are friendly targets in your raid/party). Now here is the tricky part: only 5 total people/pets can receive the WG heal within that circle, including the target of the spell. Your WG will automatically choose the 5 people/pets who are currently lowest in health (by percentage). Everyone else will, again, be left out.
Remember: this is not based on who is furthest away or closest. If they are in range of the person you cast the spell on, they are eligible, and will receive the heal if they are one of the 5 who need it the most at that moment in time. This means that it may not put a heal on your actual target: WG may instead splash on 5 people and/or pets that are lower in health than your target.
Due to this, you can choose your target carefully, selecting them not because they actually need the heal, but because they are within range of the most people who ARE in need of the heal. These targets are commonly referred to as "Bridges."
If no good Bridge is available, you can move and make yourself the Bridge. This will let you cast your WG upon yourself, and have it splash heals on the people who are in your 15-yard range.
Notice in the above diagram that there are 5 other people hit by the WG, though you targeted yourself. This means that either:
- you were the highest health out of the 6 total people in the area of effect, and so the WG applied its heal to the 5 others within your splash range and you simply served as the Bridge; or
- you picked up the Glyph of Wild Growth that is now available in patch 3.1, and so your WG can hit 6 people :)
Hope this helps!