Nurse Logs

Lichen

Nurse logs are fallen trees that serve as a vital component in forest ecosystems by providing a nurturing environment for new plant growth. As these logs decay, they retain moisture and nutrients, creating an ideal substrate for seedlings, fungi, and various microorganisms. Nurse logs help promote biodiversity by offering shelter and resources for insects, mosses, and small animals. They also contribute to soil formation and stability, playing a key role in the natural regeneration of forests.

Succession on a nurse log begins as seen in our first shot of this post. First on the scene is the lichen. Lichens along with mosses such as the “Pincushion moss”and “Streamside leptodictyum” in the next two images. create a layer of moisture retaining matter suitable for colonization by the next player in the game, the fungi.

Pincushion moss

Streamside Leptodictyum

As time goes by, the action of these organisms creates enough of a “pseudo-soil” to allow seeds from other plants such as this sweet birch to germinate and become established on the nurse log.

Sweet birch becomes established on the Nurse Log

Over the decades, the combined action of the lichen, mosses, and plants such as the birch seen above will lead to complete decay of the nurse log dispersing nutrients into the surrounding soil. Once the nurse log is completely decayed, the roots of the developing trees that developed early on may be supported as “buttresses” that grew from the tree over the supporting nurse log. When trees fall in the forest, we would be wise to let nature takes its course and let the logs remain in place rather than “cleaning” forest floor.