In nature, plants and fungi form mutualisms that allow for the “mining” of nutrients that would otherwise be unavailable to the plant. In forests, these connections between trees and fungi create large networks that allow the transfer of nutrients (nitrogen, phosphorus, and potassium) between trees through their roots and fungal structures called mycelium. These networks are called mycorrhizae and can be found in every ecosystem that plants occur.
How plants acquire nutrients belowground is an important concept for students to understand as they begin to grapple with the concepts of ecosystems and the structure of the natural world. In this activity, students will build a plant and fungal network using themselves as components of this system. The activity will be followed by reflection exercises that will push the students to answer their questions about forming an effective belowground network and why it is important for both the plant and the fungi. Fungi and trees exchange nutrients based on supply and demand. In general, large trees have a greater demand for soil nutrients than smaller trees, and thus fungi will associate more with them as they trade soil nutrients for carbon collected by the tree during photosynthesis.