\begin{center}
\begin{tikzpicture}
[
	grow                    = down,
	sibling distance        = 8em,
	level distance          = 5em,
	edge from parent/.style = {draw, -latex},
	every node/.style       = {font=\footnotesize},
	sloped
]
\node [env] {"EXPR\_OP"\\"/"}
	child
	{
		node [env] {"EXPR\_OP"\\"*"}
		child { 
			node [env] {"EXPR\_OP"\\"-"}
			child { node [env] {"EXPR\_SYMBOL"\\"arg1"} }
			child { node [env] {"EXPR\_VALUE"\\32} }
			}
		child { node [env] {"EXPR\_VALUE"\\5} }
	}
	child { node [env] {"EXPR\_VALUE"\\9} }
	;

\end{tikzpicture}
\end{center}
