Observations, of Polistes dominulus Christ feeding at Paeonia sp. flower buds, were made in the spring of 2003 and 2004 in Yakima, Washington. Y-tube and parallel tube bioassays were performed on spring queens and female workers to determine if Paeonia sp. odor is attractive to P. dominulus. Wasps were netted from their nests or while flying, kept in cages in a shaded greenhouse, and given drinking water. 48 hours before an assay, the food source, a 1:10 molasses:water solution, was removed from the cages. In the Y-tube bioassay, P. dominulus showed a significant orientation response toward fresh peony bud odor compared to the control; they did not show a significant orientation response toward fresh foliage odor. In the parallel tube bioassay, upwind movement toward fresh flower bud odor was significantly faster than to the control. Conversely, upwind movement toward fresh foliage odor was not significantly faster than to the control.