Nurse log

A nurse log is a fallen tree which, as it decays, provides ecological facilitation to seedlings. Broader definitions include providing shade or support to other plants. Some of the advantages a nurse log offers to a seedling are: water, moss thickness, leaf litter, mycorrhizae, disease protection, nutrients, and sunlight. Recent research into soil pathogens suggests that in some forest communities, pathogens hostile to a particular tree species appear to gather in the vicinity of that species, and to a degree inhibit seedling growth.^[1] Nurse logs may therefore provide some measure of protection from these pathogens, thus promoting greater seedling survivorship.

^ Mangan, Scott A.; Schnitzer, Stefan A.; Herre, Edward A.; Mack, Keenan M. L.; Valencia, Mariana C.; Sanchez, Evelyn I.; Bever, James D. (2010). "Negative plant–soil feedback predicts tree-species relative abundance in a tropical forest". Nature. 466 (7307): 752–755. Bibcode:2010Natur.466..752M. doi:10.1038/nature09273. PMID 20581819. S2CID 4327725.

[1] Mangan, Scott A.; Schnitzer, Stefan A.; Herre, Edward A.; Mack, Keenan M. L.; Valencia, Mariana C.; Sanchez, Evelyn I.; Bever, James D. (2010). "Negative plant–soil feedback predicts tree-species relative abundance in a tropical forest". Nature. 466 (7307): 752–755. Bibcode:2010Natur.466..752M. doi:10.1038/nature09273. PMID 20581819. S2CID 4327725.

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