Tilletia controversa is not present in California (US)
The report of Tilletia controversa (EPPO A2 quarantine pest) in California was based on a specimen collected by H.B. Humphrey on the 30th of June 1917 in Jacksonville, supposedly in California. After some very serious 'detective' work, it was discovered that in summer 1917, H.B. Humphrey was on a trip and that on the 30 th of June 1917, he was in or near Jacksonville, Oregon. The most likely conclusion is that H.B. Humphrey made an error in recording the locality where the specimen was collected and wrote California instead of Oregon.
Sources
Rossman, A.Y. (1994) Report of dwarf bunt from California erroneous.
Plant Disease, 78 (7), 755-756.