6th Grade · Science · Activity · shared by Luke Morgan
Learn about white-rot fungi and wood recycling in the Pacific Northwest ecosystem with this free 6th Grade Science decomposition activity.
🌲 The Life of a Fallen Giant: The Nursery Log Phenomenon
In the lush, Olympic Peninsula of the Pacific Northwest, a massive Western Hemlock tree crashed to the forest floor during a winter storm. While it might look like the end of the tree's story, it is actually the beginning of a new chapter for the entire rainforest. This fallen giant has become a nursery log , a specialized habitat that provides a home for the next generation of the forest.
Because the forest floor is covered in thick moss and heavy shade, small seeds often struggle to reach the soil or get enough light to grow. However, the top of this fallen log sits higher up, where more sunlight can reach it. As white-rot fungi begin their work, they use enzymes to break down the lignin —the tough, glue-like material that makes wood hard. This process, called oxidation , uses oxygen to pull the wood fibers apart, leaving behind soft, spongy white cellulose that holds water like a giant towel.
This soft, nutrient-rich wood becomes the perfect "soil" for new seeds. Soon, tiny Sitka Spruce and Western Hemlock seedlings begin to sprout directly out of the rotting bark. As these young trees grow, their roots wrap around the sides of the log to reach the ground below. Over many decades, the original log will completely rot away, leaving the new trees standing on "stilts" formed by their own grown roots. This cycle of forest regeneration ensures that new trees can grow even when the ground is too crowded for new life.
In the end, a nursery log serves as an ideal seedbed that recycles dead timber into a foundation for new life. As the wood softens, forest insects and other decomposers join the fungi to break the log down even further, creating shelter and rich soil that supports the biodiversity, or variety of living…