I believe this is perfect commentary on Shelleys "Ode to the West Wind." It explains how Shelley uses many metaphors and expresses how he viewed nature as a source of beauty unlike a lot of other Romantic poets during his time.
The wispy, fluid terza rima of “Ode to the West Wind” finds Shelley taking a long thematic leap beyond the scope of “Hymn to Intellectual Beauty,” and incorporating his own art into his meditation on beauty and the natural world. Shelley invokes the wind magically, describing its power and its role as both “destroyer and preserver,” and asks the wind to sweep him out of his torpor “as a wave, a leaf, a cloud!” In the fifth section, the poet then takes a remarkable turn, transforming the wind into a metaphor for his own art, the expressive capacity that drives “dead thoughts” like “withered leaves” over the universe, to “quicken a new birth”—that is, to quicken the coming of the spring. Here the spring season is a metaphor for a “spring” of human consciousness, imagination, liberty, or morality—all the things Shelley hoped his art could help to bring about in the human mind. Shelley asks the wind to be his spirit, and in the same movement he makes it his metaphorical spirit, his poetic faculty, which will play him like a musical instrument, the way the wind strums the leaves of the trees. The thematic implication is significant: whereas the older generation of Romantic poets viewed nature as a source of truth and authentic experience, the younger generation largely viewed nature as a source of beauty and aesthetic experience. In this poem, Shelley explicitly links nature with art by finding powerful natural metaphors with which to express his ideas about the power, import, quality, and ultimate effect of aesthetic expression.
http://www.sparknotes.com/poetry/shelley/section4.rhtml
