Bracon cephi and B. lissogaster are native parasitoids of the wheat stem sawfly, Cephus cinctus. C. cinctus larvae are highly cannibalistic, and when multiple C. cinctus larvae are present in a wheat stem, a parasitized C. cinctus larva which is paralyzed is more likely to be cannibalized than a healthy C. cinctus larva. Thus, parasitism can occur during the wheat growing season, but the “expressed parasitism” may be low unless all C. cinctus larvae in a wheat stem are parasitized. The “C. cinctus-parasitoid” relationship is therefore different from most other parasitoid-host systems, as the host is indirectly predating the parasitoid. Using data from seven dryland wheat fields at four locations in north central Montana we analyzed: 1) expressed parasitism in response to the level of C. cinctus infestation, and 2) the spatial distribution and spatial association of C. cinctus infestation and expressed parasitism. We demonstrate that the level of expressed parasitism is negatively associated with the level of C. cinctus infestation. The spatial distribution analyses revealed that C. cinctus infestations were significantly aggregated along field edges in 3 of 5 fields, while the expressed parasitism followed a random spatial distribution in all 5 fields. The combination of: 1) a spatial aggregation of C. cinctus infestations along field edges, and 2) a negative association between expressed parasitism and C. cinctus infestation may lower the level of expressed parasitism and therefore benefit the insect pest, as parasitized C. cinctus larvae are cannibalized by conspecifics.