Artists new to watercolor find painting trees an endless source of frustration and difficulty. They may have been told to look closely and study their subjects carefully before attempting to paint, but the more they look, the more details they see, and the more confused they become!
If you want to become an effective and talented painter, you have to make up your mind to simplify and see your subject in terms that watercolor can accommodate. This simplification is especially necessary when you are trying to paint trees and foliage. Try to look at the trees through squinted eyes: look for shapes, and disregard many of the details. Observe groups of trees, and pick out areas of light and dark. In other words, focus on creating the shape and character, the color and texture of trees, not on producing botanically correct or precise illustrations.
Individual trees are often irregular, but you can describe most of the individuals by their general shapes. If the shape is wrong, the tree will be a confusing blob that detracts from your picture. Countless varieties of trees exist, each type with its own characteristics. You need to exercise thought and care when considering how to paint your trees. They often have a more complicated shape than other elements in a painting. Nevertheless, you can simplify a tree (or group of trees) and suggest the shape as round-topped, thin and tall, conical (conifer), or even flat-topped.
Part of the difficulty with painting trees is each person’s tendency to take visual information and categorize it to fit with prior experiences. The conscious mind likes to generalize, identify, and name, then move on; thus, you end up painting what you THINK a tree looks like, the generality. Instead, to be a good artist, you need to rely on your unconscious, visual brain to actually observe and register what is before you. You can train yourself to gather the information that is normally unconscious and to then make it conscious. “Paint what you see, not what you think you see.” That is, paint what you observe, not a generalized idea of what your mind tells you a tree ought to look like. Don’t let your intellect take over the painting process if you want to avoid lollipop trees. A young child may paint a tree as a simple green circle atop a stick, but capturing a convincing image of real trees requires a bit more sophistication. (See my 12/18/2018 blog, “Painting Begins with Looking and Seeing.”)
Once you have noted the overall silhouette of the subject, look at the angle of the limbs (if the tree is close enough) and the character of the foliage. Making trees look believable has a lot to do with understanding that the primary function of the trunk and limbs is to reach up and out far enough to hold their leaves in sunlight. Each species does so in its own way, but trunk, branches, and twigs graduate in size as they get farther from the base.
Observe that the trunk grows out of the ground usually in one piece and is therefore the thickest part of the tree. It also looks more solid and stable if you curve it out at the base. From the trunk grow the limbs, which are thinner than the trunk but still need to be substantial since they bear the main weight of the tree. Try to avoid making them leave the trunk directly opposite one another. The trunk itself keeps the same thickness until a limb comes off it, whereupon it becomes less thick. The same thing happens as each limb leaves the trunk, until finally the trunk itself splits into the last two limbs. Limbs themselves split into branches, and the same reducing process goes on until branches split into twigs, which run out from the branch ends.
This tapering and meandering of the trunk branches is a little different in each species of tree, but most branches are not straight lines. Young trees tend to have smoother bark surfaces, while older trees have bark that is more textured. Try to avoid lollipop fans by painting trees with volume. Branches should spread out in all directions and grow toward (and away from) the viewer. Give branches coming toward the viewer stronger tone, tighter drawing, sharper marks, and foreshortened outlines to create more convincing trees.