Pterospora Andromedea, Pinedrops

Day 302: Three days ago, I gave a lecture on lichens and mycoheterotrophy to a group of Park volunteers. I did not include Pinedrops in the discussion because I didn't have a suitable photo of it. We also missed it during the field trip because we took a different route; ironically, this specimen was right behind the building in which I gave my talk.

The study of mycoheterotrophic plants is still fairly new; consequently, we don't have a complete map of which fungi are associated with which plants. What we do know is that the less common the fungus is, the less common the associated plant will be. This extends backwards even further because certain fungi are only associated with specific hosts, so if the host isn't present, the fungus won't be present, and therefore the plant will not be present either. In the case of Pinedrops (Pterospora andromedea), we know that its associated fungi belong to the genus Rhizopogon, including R. arctostaphylli which utilizes Arctostaphyllos uva-ursi (common names, Bear-berry or Kinnickinnick) as its host (as a sidebar here, this is a good example of taxonomy which is actually informative, which I greatly prefer to those names which acknowledge a person, i.e., if this fungus had been called R. smithii, I'd have had to do a lot more digging to find out what its associates were). Over the last decade or so, I have observed Pinedrops less frequently than in the past, certainly far less often than I did during my early backpacking years. This would seem to indicate one of two possibile contributing factors: a decrease in the fungus species and/or a decrease in the host plant for the fungus. I have not noticed a particular decline in the Arctostaphyllos population, so theory suggests that the fungal partner's needs are not being met due to some other condition; perhaps our drier summers over the last ten years have led to its diminished presence.

I've said it before, and I hope by saying it again that I wish I had another fifty years in which to attempt to find answers. The best I can hope for is to inspire someone else to pick up the research and move it forward. Fungus seems to be at the root (literally in some cases) of much of the world's diversity. We need to further our understanding of the mycorrhizal connection to life.