Biology researchers discover that bacteria living in mosses on tree branches twice as effective at 'fixing' nitrogen as those on the ground

Moss-covered old oak tree (Quercus petraea) in temperate rainforest

"You need trees that are large enough and old enough to start accumulating mosses before you can have the cyanobacteria that are associated with the mosses," Lindo said. "Many trees don't start to accumulate mosses until they're more than 100 years old. So it's really the density of very large old trees that are draped in moss that is important at a forest stand level. We surveyed trees that are estimated as being between 500 and 800 years old."


https://www.sciencedaily.com/releases/2011/06/110607121144.htm