Forest Expanses belongs to the period during which Shishkin tackled the problems of plein-air painting. While preserving the epic scale of nature portraits, his painting became more gentle and free. When painting Ural landscapes, Shishkin chose a high vantage point, which was unusual for him. He did not want to paint the concrete location, but rather create the image of a whole country. He divides space into a series of different grounds: by drawing the viewer's gaze to the silver lake at the centre of the painting, he gives the impression that the forests are floating and drifting towards and away from one another, in a manner reminiscent of the waves in Aivazovsky's seascapes. According to Shishkin, the forest is a basic element of the universe, along with the sea and the sky. One critic wrote in connection with this painting: "The distant perspective of forests covered in light mist, along with the surface of the water in the distance, the sky, the air, in a word, the complete panorama of Russian nature, whose beauty is discreet, is represented on the canvas with remarkable mastery."