Today marks another first for the Botany Photo of the Day–first photograph from someone not affiliated with UBC. This photograph was forwarded to Judy Newton, the garden’s education coordinator (in 2005), from a personal friend to see if Judy or someone else at the garden could identify the plant. With a little help from Holmgren’s Illustrated Companion to Gleason & Cronquist’s Manual of the Vascular Plants of Northeastern United States and Adjacent Canada, we were able to positively identify it as Conopholis americana (usually, I post emailed ID requests to our Plant Identification Discussion Forum so everyone can learn but since it is being shared on Photo of the Day, that isn’t necessary).
Conopholis americana is commonly known as American cancer-root, and is distributed throughout eastern North America. This photograph is from a few days ago, and was taken by Sam Roberts. American cancer-root is a member of the Orobanchaceae, and like most members of that family, it lacks chlorophyll and is wholly parasitic, in this case stealing nutrients from the roots of woody forest plants. Some orobanchaceous plants are only partly parasitic with a partial reliance on chlorophyll, like Castilleja hispida var. hispida, featured previously on Photo of the Day.
Apparently, the ancestral plant of this family was either non-parasitic or partially parasitic, as it seems the strategy of being completely parasitic evolved on more than one occasion within the family (for references, see the Angiosperm Phylogeny Group entry on Orobanchaceae).