I think you have a pretty good start here, actually. Your perspective on the path, the fences and trees trunks is pretty good. You could make the closer trees a little larger in trunk size, and play with the greenery some.
What I think you are missing, is value changes in your colors. When everything is the same value it creates a sense of flatness. You can add different shades of green to the grasses. You can change the value of your sky from top to horizon. You can have your
ick path be more detailed in the foreground. Things like that will help you add depth.
You may also want to think about which direction your light is coming from, and create shadows in the appropriate places (trees, fences, etc.)
Don't give up. Stay after it and keep working on it. You'll get there!