This thesis is an exploration into how trees are perceived by professionals associated with landscape architecture. It is argued that perceptions influence the decisions that we make, therefore the aim of this study was to explore the range of perceptions of notable landscape architects selected for their varied expertise. Fifteen participants across North America were interviewed using a semi-structured interview method. Interview transcripts were analyzed using content analysis and responses were categorized into three themes: influence, perceptions, and action. The results suggest that participants have a wide-range of perceptions of trees in their scholarship and practice. Most notably, perceptions ranged from a tree as a tool, to a tree as a living thing, to a tree as something personal. Based on the results of this study, it can be concluded that a range of perceptions of trees may influence professional practice in the planting design decisions that landscape architects make.