  Holomorphic 2-forms on K\"{a}hler surfaces lead to "Local Gromov-Witten
invariants" of spin curves. This paper shows how to derive sum formulas for
such local GW invariants from the sum formula for GW invariants of certain
ruled surfaces. These sum formulas also verify the Maulik-Pandharipande
formulas that were recently proved by Kiem and Li.
