Trees only blend into a single shape from a distance, but even then there’s usually some variation in texture or color that makes the image more interesting. Look for ways to suggest distance.
Don Gore used a single ink pen to express the gestalt of these evergreen trees. The spiky, scratchy feeling is perfect for their texture.
Let your brush marks suggest the foliage of specific trees. Shevaun Doherty captured the feel of olive trees with hundreds of small, quick marks, and carefully observed the growing patterns, as well.
I often make my pages do double duty. Here, I was trying out new paints (at the top) but didn’t want to waste the page. A trip to Cooley Lake tempted me to paint that simple blue distance. The hill to the left was much closer, so I used texture and variation in color to suggest the trees there, and the bare winter trees in the foreground got a simplified but more detailed handling to bring them forward.
Carrying masking fluid in the field can be tricky, but some companies make a needle-point applicator that makes it a lot easier and safer. (I once turned a whole bottle of the stuff over on the rocks I was painting!) Here, I protected the fine limbs of the dead tree, and painted in the background loosely. When that was dry, I removed the mask, painted the trunk and softened some of the limbs with clear water so they didn’t look so pasted on. Then I scratched out even finer twigs with a sharp blade.
I didn’t create much detail in the background, only enough to suggest the idea of forest. Spatter, scraping and a few tree trunks let the foreground tree pop.
If you prefer, sketch a detail you may find at your feet, like this twig, leaf and acorn from an oak. Take as long as you want.