Soil fungal sampling
Soil samples were collected from each experimental plot from August 25-28, 2020 using a 2.2 cm diameter soil sampling probe. The surface plant litter layer was removed, and four soil cores per plot were extracted to a depth of 10 cm. The four cores were composited and homogenized using a 2 mm sieve and roots were removed. Soil probes and sieves were sterilized with bleach between plots to reduce the chance of cross-contamination. Soils were then frozen at −20°C until DNA extraction.