Not all landscape drawings and paintings need to be totally realistic. Many of the best are far from it. They give only the impression of the landscape. Or the idea or are simply inspired by and area. The idea takes on a life of its own.
In drawing, this is more than true. You are representing a landscape, but of necessity, editing and changing it. With pencils things are reduced to grayscale. With pen and ink, literally black and white, or simply tinted and stylized.