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Chesapeake Peninsula in October and examined the field ex- 

 periments under progress. Dr. E. F. Smith is the special agent 

 of the Department of Agriculture, who is investigating the 

 disease. In this region he has eighty acres of orchard under 

 direct experiment, forty of which, scattered through twelve or- 

 chards in Delaware and Maryland, are devoted to fertilizer tests. 

 These fertilizer tests are above a hundred in number, and com- 

 prise treatment with nitrogen, potash, and phosphorus, and many 

 combinations of them. He has tried all of the fertilizer remedies 

 which have been recommended for the cure of the disease and for 

 its prevention. These have been tried upon all kinds of soils, 

 and upon trees of all ages. They have been used with exceeding 

 care, and they comprise the largest field experiments of this na- 

 ture, upon diseases of plants, yet made in this country. It is 

 evident upon examining these orchards that there is no fertilizer 

 nor combination of fertilizers which will either cure or prevent 

 the yellows. Many of the fertilizers, especially those rich in ni- 

 trogen, have a wonderful effect upon the vigor of the tree, but 

 they do not prevent the yellows, nor cure it. All the investi- 

 gations so far made, go to show that yellows is a specific disease, 

 entirely independent of soil or surroundings. 



Many investigations in other directions have been made, and 

 many important facts have been obtained concerning the nature 

 of the disease, but so far its cause has not been determined. The 

 disease is an exceedingly obscure one, much more so than pear 

 blight or any other disease with which we are familiar. 



The New Jersey, Delaware and Maryland orchards are being 

 rapidly decimated with the yellows ; in fact, the upper portion 

 of Delaware is practically devastated of peach trees, and the upper 

 part of the Chesapeake Peninsula in Maryland is no longer a 

 profitable peach region. There are acres upon acres of orchard 

 in which more than every other tree is visibly diseased, and in 

 large areas it is almost impossible to find a single healthy tree. 

 There has been very little united attempt toward controlling the 

 yellows in these regions, and for that reason this present destruc- 

 tion threatens the industry. It is useful to compare the results 

 in this region with those of the Michigan peach region, where a 

 definite law was early enacted ami which lias been enforced vigor- 

 ously. In Michigan the yellows is on the decrease and the plant- 

 ing of orchards is on the increase. In Maryland and Delaware, 



