Decided against the underwater theme half way through as it wasn't tree-like enough and didn't make much sense. The bendy looking branch was meant to be a dying branch but it doesn't look right.
Wanted to try and do a better version of this as my previous attempt was extremely rushed and I changed my idea halfway through. I used a mangrove tree I made for use in the group game project as a base and did a render of it. Looking back I probably should of removed the planes with the leaf textures on so I could of painted new leaves instead of painting over the ones I had
Final: Added the sky using a gradient and a cloud brush, then adjusted the levels, added a base brownish colour to the plane and then used a rock brush to paint over everything which I then used a perspective transform on to give a sense of depth. I added some more leaves and added shadows and lowlights to these I also painted the bottom of the tree to look more like roots and as if its in the ground. I added some extra foliage in the background using brushes and added extra shadows and highlights to the trunk. After this I added a shadow using a brush, the outline of the shadow looks too harsh though so I should of used the burn tool as this would of given a softer more realistic effect. Finally I used selective colour filter to adjust the colours then used dodge and burn on the ground to get a more varied appearance. I was intending on making a swamp scene but ended up with a scrub/savannah instead.