--- a/git-branches.tex
+++ b/git-branches.tex
@@ -43,3 +43,38 @@
 
   \end{itemize}
 \end{frame}
+
+\begin{frame}{Deleting a Git Branch}
+  \tikzstyle{rev}+=[on chain, minimum size=5mm]
+  \tikzset{node distance=10mm and 12mm, on grid}
+
+  Git can \alert{garbage collect} changesets:
+  \begin{itemize}
+  \item repository with experimental branch:
+
+    \begin{tikzpicture}[start chain]
+      \path (0, -1) rectangle (6, 1.5);
+      \node[rev, join] {};
+      \node[rev, join] {};
+      \begin{scope}[start branch=pulled]
+        \node<1>[rev, join=by join-nw, on chain=going above right] {};
+        \node<1>[rev, join] {};
+        \node<1>[rev, join, pin=right:experiments] {};
+
+        \node<2->[rev, opacity=0.3, join=by {join-nw, black!30!white},
+          on chain=going above right] {};
+        \node<2->[rev, opacity=0.3, join=by {black!30!white}] {};
+        \node<2->[rev, opacity=0.3, join=by {black!30!white}] {};
+      \end{scope}
+      \node[rev, join] {};
+      \node[rev, join, pin=below:master] {};
+    \end{tikzpicture}
+
+  \item<2-> delete branch with \cmd{git branch -D experiments}
+
+  \item<2-> faint commits  may disappear on next \cmd{git gc}
+
+  \item<3-> \alert{delete on server} with \cmd{git push origin
+    \alert{:}experiments}
+  \end{itemize}
+\end{frame}