In "Road to Somewhere", above, I spent as much time if not more creating interesting negatives. My positive shapes are the small hills on both sides of the road and the road itself. All the remaining shapes including the fields, roadside grasses and sky are subordinate or negative. However, note how interesting each of these shapes are. They are quite clearly, part of the whole and what creates the "finished" quality and unity in the painting. Without them, this painting would have very little impact. The are effectively important to the overall look of this work.
So, the next time you find yourself struggling with your subject, take a moment and look at the negative space around it. You just might improve that tree or building by creating a better negative.