Winter 2005-2006, either Dallas or Webster County: Iowa DNR raises prairie seeds; harvests, cleans and distributes them for planting on public land. The inmates and I were hand cleaning seed when I noticed swellings in the Silphium laciniatum, compass plants. I opened a couple and found larvae so asked the guys to look for more. The swellings were put into a jar. Eventually wasps emerged. Since this was one of the first insects I reared, I had yet to learn to keep records.

John Tooker wrote: "I am familiar with the gall wasps you have found. They are in the genus Antistrophus, and if they came out of the heads of Silphium laciniatum (compass plant), they are probably Antistrophus laciniatus, which was a very common species in central Illinois. If you have found wasps in the flower heads of S. perfoliatum (cup plant) that would be very interesting to learn because such a host record has not been reported. I have found similar wasps in S. terebinthinaceum, but not that many despite some effort."