Let $G = (V,E)$ be a finite graph, allowing loops and parallel edges, and let $e \in E$. Let $M(G)$ denote the graphic matroid on ground set $E$, whose independent sets are precisely the edge subsets $F \subset E$ such that the spanning subgraph $(V,F)$ is a forest. Then, under the natural identification of ground sets with $E \setminus \{e\}$,
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\begin{align*}
M(G) \setminus e = M(G \setminus e).
\end{align*}
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Moreover,
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\begin{align*}
M(G) / e = M(G / e),
\end{align*}
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where, if $e$ is a loop edge of $G$, the graph contraction $G/e$ is interpreted as $G \setminus e$, matching the matroid convention that contracting a loop has the same effect as deleting it.