Class 1. Bacterial agents: 
Agrobacterium - All listed species: A. rubi 3 A. radiobacter 3 A. 
tumefaciens 3 A. rhizogenes 
Corynebacterium - Most plant pathogenic species except as regulated 
by Class 2 or Class 3 plant pathogens. 
Erwinia - All plant pathogenic species except those in Class 2 or 
Class 3 and when the host, that is commercially propagated 
is present in the state, e.g., E. amylovora is a class 
II agent in California where the host is grown in large 
units of land but is Class I in Nevada where the host is 
not cultivated. 
Pseudomonas - All plant pathogenic species except those species 
restricted as Class 2. 
Xanthomonas - All plant pathogenic species except those restricted 
in Class 2 or Class 3. 
Class 2. 
All Corynebacterium species where their respective hosts exist and where 
climatic conditions favor the disease. For example, C. michiganense in 
tomato growing regions, C. sepedonicum in potato growing regions (Idaho, 
California) . 
All Erwinia species where their respective hosts exist and where climatic 
conditions favor the disease. For example, E. amylovora in regions cul- 
tivating apples and pears (e.g., California, Oregon, Washington, New 
York, Maine). 
All Pseudomonas species where their respective hosts exist and where 
climatic conditions favor the disease. For example, P. lachrymans in 
regions cultivating cucumber (e.g. Wisconsin, Ohio), P. 
solanacearum in tobacco states (e.g., North Carolina, Virginia, Kentucky). 
All Xanthomonas species where their respective hosts exist and where 
climatic conditions favor the disease. For example, X. malvaceamum in 
regions where cotton is cultivated, (e.g. Texas, Arizona, 
Mississippi . ) 
Class 3. 
Species that are under quarantine in the United States. Species cannot 
be brought in from foreign countries. For example, Xanthomonas citri 3 
X. oryzae 3 Erwinia vitivora. 
[Appendix A — 101] 
