PollyMapSmut mold spore photographed through the microscope in the PollyKit lab — verified in Arizona.
More verified photos of Smut
About smut spores
Small, dark, thick-walled spores from smut fungi that infect grasses and grain.
Where it grows
- Infected corn, wheat and other cereals
- Wild and pasture grasses
- Stored grain and dust from harvest
How to recognize it
Small round to oval spore with a dark, evenly granular or minutely warty thick wall and no internal divisions or pores.
Typical published size: 5–15 µm
Commonly confused with
- Grass pollen — larger with a ringed pore
- Rust spores — larger, often spiny
- Nettle pollen — has pores
Allergy relevance
Mild to moderate allergen; most important for farm and grain workers and during harvest, when concentrations spike.
Where it's found
PollyMap has verified specimens of Smut from Arizona.
Worldwide in agricultural and grassland regions.
Also searched as: smut spore, ustilago spore, smut spores under microscope, cereal smut.
Related mold specimens
Citing this specimen: PollyMap Specimen Library. “Smut — verified microscope specimen.” pollymap.com/library/specimen/smut-mold-spore-70a9a0
Expert discussion
No published comments yet. If you study palynology or mycology, we'd value your read on this specimen.