Outbreak of Puccinia horiana in California, US
Puccinia horiana (EPPO A2 quarantine pest) had been thought to be eradicated from the USA since its outbreak in 1991. In 1993-03, however, chrysanthemum white rust had been detected again at 17 residential properties in the Santa Cruz County in California. Previous findings of P. horiana were always confined to nurseries. Plant protection authorities in the USA have removed and destroyed all chrysanthemums from the affected residential properties.
Sources
NAPPO Newsletter 1993-07, Vol. 13 (3), p. 10