ADDITIONAL EVIDENCE ON THE COMMUNI- 



OABILITY OF PEACH YELLOWS 



AND PEACH EOSETTE. 



PART I.— PEACH YELLOWS. 

 I. — INTRODUCTORY. 



Destructive nature of yellows. — Peach yellows is a perplexing and 

 destructive disease. On all hands it is conceded to be one of the most 

 serious with which American fruitgrowers have to contend. Formerly this 

 disease was confined to a small district on the Atlantic coast, but during 

 the last twenty years it has invaded distant regions hitherto free, and has 

 entirely ruined the peach industry over very considerable areas. Within 

 ten years the disease has taken a fresh and very strong hold upon orchards 

 in the Delaware and Chesapeake region, the north portion of the penin- 

 sula, and has destroyed thousands and thousands of trees, rendering a 

 great industry unprofitable or precarious. It seems to be native to the 

 eastern United States, having, so far as we know, not been reported from 

 California. Diligent inquiry also has thus far failed to bring to light any 

 notice of its occurrence in Europe or other parts of the globe. 



The last negative evidence is from Mr. Newton B. Pierce of the divis- 

 ion of vegetable pathology. From May to October, 1890, he was in Medi- 

 terranean countries investigating vine diseases. Mr. Pierce traveled ex- 

 clusively in France, Italy, Sicily, and Algeria, and looked carefully for 

 this disease. He examined peach trees in a great many localities, and ob- 

 served the fruit in the principal markets, but failed to find any traces of 

 yellows. Inquiries of many persons devoted to the scientific study of 

 agriculture and horticulture also proved fruitless. They had not seen or 

 heard of anything resembling this disease. 



The distribution of the disease and the losses occasioned thereby were 

 set forth somewhat fully in my first bulletin and do not concern us at this 

 time. It is propor to state, however, that the losses continue in the infected 

 districts; that the disease has appeared in new localities; and that 

 regions now healthy are also threatened. Yellows is certainly as far south 

 as southern Virginia and probably as far west as Arkansas and northeast- 

 ern Texas. Peach-growers are earnestly advised to stamp out the disease 

 upon its first appearance, and are warned against the importation of trees 

 from infected districts. These remarks apply with especial force to the 

 Pacific coast, and in this connection it is well to remember that the apri- 

 cot and almond are also subject to yellows. It would be much safer for 

 the Californians to grow their own peach trees than to introduce any from 

 the eastern United States. If trees are imported, it should be known 



