August 4, 2009
Indian Pipes, Monotropa uniflora
This has been a good year for Indian Pipes: an unusually large number have been seen at Fresh Pond Reservation and elsewhere. Because they are white, Indian Pipes might be mistaken for fungi, but they are actually flowering plants in the family that includes blueberries. They contain no chlorophyll, and do not require light for growth.
The mystery of how they survive was solved with the help of radioactive carbon dioxide. When the leaves of a small tree near some Indian pipes were exposed to the CO2, the radioactivity traveled down through the roots of the tree, into the micorrhizal fungi associated with the roots, and then into the Indian Pipes. Although the association between trees and micorrhizal fungi appears to be mutually beneficial, apparently the Indian Pipes are getting a free ride, giving nothing back to the tree or the fungi.