  We construct small resolutions of the moduli space $\overline{Q}_n$ of stable
scaled $n$-marked lines of Ziltener and Ma'u--Woodward and of the moduli space
$\overline{P}_n$ of stable $n$-marked ${\mathbb G}_a$-rational trees introduced
in earlier work. The resolution of $\overline{P}_n$ is the augmented wonderful
variety corresponding to the graphic matroid of the complete graph. The
resolution of $\overline{Q}_n$ is a further blowup, also a wonderful model of
an arrangement in ${\mathbb P}^{n-1}$.
