PEACH YELLOWS. 253 



There is no question but that the root-aphis has killed thousands of trees, 

 and been in some sections a very serious obstacle to successful peach culture, 

 although it is not so much to be dreaded as the yellows. The marked feature 

 throughout is the stunting, something which is not a precursor of yellows nor 

 cliaracteristic of the earlier stages of that disease. After a year or two of 

 languishing such trees also not infrequently recover. Upon none of them 

 have I seen premature, red-spotted peaches and the characteristic diseased 

 shoots except when the tree was also suffering from yellows. 



(3) The peach nematode. — A species of Anguillula infests the roots of peach 

 trees in Florida and probably also in some other portions of the country, al- 

 though I have never observed any on the Chesapeake and Delaware peninsula 

 or in the peach districts of Michigan. This minute worm produces knobby 

 enlargements and excrescences on the smaller roots, in which usually the cysts 

 of the parasite may be detected. In this way the roots are often badly injured, 

 and the tops become yellow and die, but, so far as I can learn, with no symp- 

 toms peculiar to yellows. I have seeen only the infected roots. 



(4) Decay of roots. — Southwest, in Arkansas and Texas, the peach is reported 

 to suffer considerably from root rot. In what way this affects the parts above 

 ground or whether its manifestations are likely to be mistaken for yellows I 

 am unable to say. 



(5) Starvation. — Trees set upon pure sand or upon peat make a very feeble 

 growth, although usually managing to live for some time. This starved con- 

 dition, which readily disappears when suitable fertilizers are applied, 

 might possibly, also, be mistaken for yellows, although I do not think 

 it very likely, as such soil is generally well known to be barren and will not 

 grow any fruit trees satisfactorily. Certainly this trouble would never be con- 

 founded with yellows by any person familiar with that disease. 



(6) Yet subsoil. — Sometimes, by inexperienced growers, peach trees are set 

 upon cold, wet soils. If these trees do not die outright they grow very slowly 

 and produce only dwarfed yellowish foliage. I have seen such cases in a 

 number of orchards, and believe the sickly appearance was due entirely, or at 

 least primarily, to the nature of the soil. Few persons would, I think, be 

 likely to mistake this for yellows. The premature peaches and the diseased 

 shoots are wanting, and the unfavorable situation is a sufficient explanation 

 of the symptoms which do appear. 



Mr. Smith's next chapter is devoted to "Losses Due to Yellows," and he 

 gives details of ravages in many orchards in Delaware and Maryland; but on 

 this point Michigan peach growers scarcely need more information than they 

 already possess from their own experience. 



To resume Mr. Smith's report : 



EXTENT OF THE PEA.CH INDUSTRY IN THE UNITED STATES. 



The peach is, by common consent, the choicest fruit of middle latitudes, 

 and is cultivated in both the north and south Temperate Zones the world 

 over; but nowhere else in such enormous quantities as in the United States. 

 Notwithstanding this, since facilities for drying and canning on a large scale 

 have become general, there is a demand for the entire product of even the 

 most prolific years, and indirectly the industry has thus become one that 

 interests all parts of the country. 



The districts of the United States and Canada now chiefly interested in the 

 production of this fruit are the following: Southern Connecticut, southeast- 



