Okay, quick couple of things.
Firstly, the environment is very good. There's a very nice use of both foreground and background, and background moving to foreground giving a good sense of 3D space.
As far as drawing forests go, I'm no expert, but the thing to initially take into account is that you don't draw trees, you draw a forest. When you're looking at a forest you never take each individual tree into account, it's more a mess based on the collective shape, if that makes any sense.
The major thing I'd keep an eye on here is the composition. I think you need to take better care with keeping things consistent and balanced: Blaze's eyes are two different shapes and she looks a little lop-sided - her left hair tufts (our right) should probably be shorter, as they're mainly hidden behind her head, that sort of thing. This also kind of extends to the lines - it's very clean linework, but I would try playing a lot looser with it to make it less... lumpy? Try varying their weights and keeping them more streamlined to make it look more natural. Maybe try using other brushes as well, if you're using Photoshop? (I can send you a bunch of really ace brushes if you'd like).
Anyway, good work overall, great to see you drawing again, dude.