For a graph $G = (V, E)$, the $γ$-graph of $G$, denoted $G(γ) = (V(γ), E(γ))$, is the graph whose vertex set is the collection of minimum dominating sets, or $γ$-sets of $G$, and two $γ$-sets are adjacent in $G(γ)$ if they differ by a single vertex and the two different vertices are adjacent in $G$. In this paper, we consider $γ$-graphs of trees. We develop an algorithm for determining the $γ$-graph of a tree, characterize which trees are $γ$-graphs of trees, and further comment on the structure of $γ$-graphs of trees and its connections with Cartesian product graphs, the set of graphs which can be obtained from the Cartesian product of graphs of order at least two.