Imagery is an important part of "The Buck in the Snow," used by the poet to engage the reader and set the scene, and also to establish important symbolism.
In the first stanza, Millay uses imagery to create a rich setting for the poem. The speaker describes a quiet, wintry landscape filled with snow. There are evergreen "hemlocks bowed with snow," an "antlered buck and his doe," an "apple-orchard," and a "stone-wall." This imagery seems idyllic and peaceful, a simple scene of a buck and his mate, two animals in the prime of their lives. When the deer leap, the speaker observes that their "long leaps" are "lovely and slow," a description that emphasizes the animals' power and grace.
At the same time, however, some of this imagery is also foreboding. In line 1, the speaker addresses a "White sky," implying that the sky above is not clear and blue but rather cloudy and filled with the potential for snow. Snow arrives with the winter, a barren season symbolically associated with death. The landscape's abundant snow and the watchful white sky, therefore, suggest death lurking in the background of the otherwise lovely, peaceful scene.
In keeping with this, the hemlocks in the scene are "bowed with snow." Hemlocks are an evergreen tree, meaning that they do not lose their leaves in the winter; their presence suggests the perseverance of life even in the harshest of seasons, yet here the trees sag under the weight of the snow—under the heavy presence of death.
The imagery of the second stanza brings that sense of foreboding to fruition. In line 6, the buck, so lively just a short time earlier, lies dead before the speaker, "his wild blood scalding the snow." The imagery here establishes the sharp contrast between the heat of the buck's "wild blood," essentially representing his life force, and the coldness of the snow, representing death. There is also an implied striking visual contrast between the redness of the blood and the pure whiteness of the snow. These contrasts—between red and white, between heat and icy cold—reflect the symbolic opposition between life and death.
The third stanza of the poem confirms the power of death over life. In lines 7-8, the speaker describes death "bringing to his knees, bringing to his antlers / The buck in the snow." A buck that has fallen to his "knees" and "antlers" is a buck that has lost a fight. This image thus illustrates death's conquest of the mighty buck—again establishing the power of death over all life, no matter how virile and strong that life may seem.