I did the underpainting in a layer of Raw Umber. I've tried other colours for underpaintings in the past, but I always end up coming back to raw umber. It dries quickly for an oil paint, and I find that the green-brown tinge to the colour really enhances any other colours added over top.
Once the underpainting was dry, I started adding in the forest colours using Prussian Blue, Sap Green, and Viridian Green. The pathway was a combination of Raw Umber, Burnt Umber, and Van Dyke Brown. I also used the same colours for the pathway on the trees in the distance.
At first I put the paint on as thin as possible with a hogs hair brush. Since the stretched canvas has a texture to it, I find that hogs hair brushes are great for filling everything in without leaving little white specks from the canvas's texture.
Once the basic idea of colour was on the canvas, I started adding in detail with smaller softer, round tipped brushes. I did this while the paint was still wet. I left some of the underpainting showing through on the up-close trees because I liked the way the umber underpainting looked underneath.
I added in Permanent Green to some of the highlights on the leaves in the distance.
The ferns were a lot of fun to paint. I added in extra Prussian Blue to the shadows, and Permanent Green and Titanium white to the highlights. I used a little Green Earth on the fallen stumps and forest floor.
The rest of the forest was done using the same colours as I mentioned above. The Colour was all one layer, wet in wet.
This painting was created using Grumbacher Pre-Tested oils. Grumbacher was the only name brand I used to use for my paints, but lately I have also been using Gamblins and Winsor & Newton.