Bermuda Smut
Ustilago cynodontis
Photographed in Phoenix, Arizona 7 May 2007. This photo is also
hosted at Wikimedia
where there are additional images of
Corn Smut, Ustilago maydis.
Another smut fungus species in a grain of Pleuraphis rigida, Big Galeta. The mature spores fill the seed hull which ends up growing several times larger than usual. The spores are black, appearing like soot. Photographed in s.w. Maricopa Co., Arizona, USA. Sept. 2009.
Cool, moist weather late in the spring after Bermuda Grass (Cynodon dactylon) has begun flowering seems to lead to seed heads becoming infected with the smut fungus, Ustilago cynodontis. These infected heads are mostly seen in the urban areas of the Sonoran Desert and are readily identfiable by the copious, jet-black, sooty spores. The spores of smut fungus are released into the air for dispersal and contribute to allergies in susceptible people.