Andrew Ratz

While most mushrooms cast their spores to the wind, truffles have evolved to stay underground. They release strong scents and can mimic berries or nuts, leading to the long-standing assumption that they are strictly animal-dispersed.

However, our recent findings of high truffle spore concentrations in the atmosphere suggest we have been ignoring a major piece of the ecological puzzle: airborne truffle dispersal. By re-examining this subset of the aerial fungal community, we argue that, while not the primary mode of transportation for these fungi, the wind may play an important role in carrying these grounded fungi further than any animal possibly could.

Fungi are vital ecosystem drivers, along with delectable and wondrous organisms, yet their dispersal via microscopic airborne spores remains a challenge to study. This talk bridges the gap between visible mushrooms and the "invisible" fungal atmosphere. By employing passive spore traps and ITS1 DNA sequencing at multiple sites across the United States, we characterized macrofungal communities across eight diverse ecoregions.

We also compared these airborne data with local fruiting observations from field surveys and iNaturalist to determine the "effective input range" of spores. Our results reveal that while climate and regionality are the dominant drivers of spore diversity, nearly 50% of captured spores originate from mushrooms within a ~20 km radius and community similarity was determined by the habitats found within a few kilometers. These findings clarify the scale-dependent link between local fruiting and the broader patterns of fungal migration and biogeography.