Book 24, Question 63
What are the thin threads of a fungus that spread underground?
The main body of most fungi is a mass of super-thin threads called mycelium. Each thread is much thinner than a hair, but together they form a web that spreads through soil, wood, and leaves. The threads release chemicals that break down dead material and then absorb the nutrients. In a teaspoon of forest soil, there may be miles of threads.