Ecologist Suzanne Simard revolutionized forestry science with her groundbreaking research, challenging the long-held belief that trees are isolated individuals fiercely competing for resources. Driven by observations that the Douglas fir trees would sicken after foresters removed paper birch trees—which were considered invasive weeds—Simard’s doctoral work in the 1990s used radioactive carbon isotopes to trace nutrient movement. She discovered that birch and fir trees were not merely competing, but were linked together by a vast, complex mycorrhizal network (which she nicknamed the “Wood Wide Web”) of underground fungi, which acts as a two-way pipeline. This network allows the birch to pass essential nutrients, including carbon, to the fir, especially when the fir is shaded, effectively mitigating the competitive effects and maintaining the overall health and ecological balance of the forest ecosystem.