12 PEACH YELLOWS. 



Arkansas and northeastern Texas. Peach-growers are earnestly ad- 

 vised 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 apricot and almond are also subject to yel- 

 lows. 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 beyond question that they 

 are from regions where this disease does not occur. The mere fact 

 that the nursery stock is healthy at the date of shipment is not a 

 sufficient guaranty that it will continue so. 



(2) Characteristics of the disease. The primary and peculiar symp- 

 toms of peach yellows are only two: (1) The red spotting and abnor- 

 mally early maturity of the fruit; and (2) the premature germination of 

 ordinary winter buds, or of obscure buds buried in the bark of the trunk 

 and limbs or formed in the cambium. All other symptoms result from 

 these, or are only the common indications of disease and decay in plants. 



Plate I represents two peaches, natural size, one healthy and the other 

 diseased. They are of one variety and were gathered the same day. 

 They were picked from neighboring trees, but might have come from 

 the same tree, since in the first stages of yellows both sorts are usually 

 found upon the same tree. The unspotted peach (Fig. 1) was hard, 

 green, and normal in all respects. It would not have ripened under two 

 weeks. When ripe its skin would have been creamy white with a blush 

 on one cheek, composed of very minute and nearly uniform crimson puuc- 

 tations. Its flesh would have been melting and juicy, slightly acid, aro- 

 matic, and delicious. The color of the flesh would have been uniformly 

 white, except for a narrow zone of crimson immediately surrounding the 

 stone. The diseased peach (Fig. 2) was fully ripe. Its size was normal; 

 its color, abnormal. The skin was beautifully mottled and blotched with 

 crimson, giving an appearance quite unlike that of healthy fruit. Many 

 of these spots were large enough and sufficiently unlike the rest of the 

 skin to admit of being easily photographed. The flesh was also copi- 

 ously streaked and spotted with crimson. On tangential section these 

 brightly colored portions were usually oval or roundish ; on radial sec- 

 tion they appeared more often in the form of streaks or elongated spots. 

 There was also more than the usual amount of color around the stone. 

 The flavor of the peach was inferior. This diseased peach was only one 

 out of thousands occurring that year in the infected districts. High- 

 colored, premature fruits are one of the conspicuous symptoms of the 

 disease, and are easily distinguishable even from a car window. Iti 

 July, 1891, I saw hundreds of bushels of this worthless fruit in upper 

 Maryland and Delaware, and the entire loss thereby in 1891 certainly 

 exceeded half a million dollars. 



The amount of color appears to depend somewhat upon variety. 

 Sometimes there is comparatively little crimson spotting, and again, 



