In comparison with Ibervillea lindheimeri: Cissus on the right, Ibervillea on the left. Last photos is just Cissus.
Seedlings germinated in old flower head
During vegetation surveying for the Wildflower Center's long-term ecological experiment. Seeds germinating out of an old flower head. The only flower heads we found in the area were of Rudbeckia.
@kip_lary obtained some excellent macro shots here: https://www.inaturalist.org/observations/189262123