Piegan Glacier 2009.

These photographs document another aspect of Glacier Park’s dynamic environment, vegetation change. Although Piegan Glacier has not melted noticeably, years of fire suppression and changing climate may have allowed the invasion of conifers in what was an open meadow in the foreground of the 1930 photo. Also, the demise of the ecologically important whitebark pine (Pinus albicaulis ) is visually...