HISTORY OF TREATMENT. 47 



of the Aj'x/.^ntr, thiit it hiis hi'cn proved that tlu- inyrcliuiii winters 

 over in the yoiiiio'est parts of the shoots and in the huds, and he 

 reooiiiinends the removal of isohited sligfhtlv diseased leaves soon after 

 the first appearanee of the l)lister-lik(> swellings. When through the 

 attaek of a majority of the lea v'es of a branch it is shown that the 

 mycelium is already present in the axial organs, it is advised that all 

 of the vouno- wf)od of the affected branches be cut off. Hartijjf de- 

 scribed peach leaf curl in 1S81),' and agaiji in th«^ English edition of 

 his work pu])lished in ISH-t," but he leaves the su))ject without making 

 any suggestions as to treatmcMit. In 181K) Dr. Kirchner pul)lished 

 a work on plant diseases,'' in which he reconunends the cutting off of 

 diseased branches for the control of the disease. In 1801. Dr. Comes, 

 in writing of this disease, states that no direct means for combating 

 the parasite exists. He discusses the gathering and burning of dis- 

 eased and fallen leaves, the cutting back of infected branches, and the 

 application of cultural methods it) tluMr influence on tlu^ disease,* A 

 most excellent work on plant diseases by Dr. Tubeuf appeared in 

 1895,^ This writer groups the diseases caused by the /u'<>t/sr,'(i> among 

 those maladies which should ))«> coml)ated by the removal of the 

 diseased living plants and plant parts (pp. 8(5, sT). The second edition 

 of Frank's work on plant diseases appeared in 18iM», fifteen years 

 after the publication of the first edition, but the same recommenda- 

 tions for the treatment of curl are again made, word foi' word.^ In 

 all the preceding works there is no recognition of the methods of treat- 

 ment ])eing adopted and discussed in the United States and in Aus- 

 tralia. The recommendations for cutting away the diseased branches 

 so generally presented are the same as advanced l)y EhrcMifels nearly 

 a century before for the control of mildew of the peach.' 



It is hardly necessar}' to say here what most orchardists ha\'e learned 

 by experience, that is, that it is impossible to eliminate the disease by 

 ordinary cutting back of the branches, and that in the orchard it is 

 equally impracticable to prevent the disease by the early removal of 

 the diseased leaves. 



About this time the work being done on this disease appears to have 

 attracted the attention of Europeans. In 1891, in his work on. vege- 

 table parasites, Berlese recommends for this disease in Italy the use 



^ Hartig, Dr. Robert, Lehrbuch der Baumkrankheiten, Berlin, 1889, pp. 118,119. 



-Idem, The Diseases of Trees, London, 1894, pp. 132, 1.33. 



'Kirchner, Dr. Oscar, Die Krankheiten nnd Beschiidigungen unserer landwirt- 

 schaftlichen Kulturpflanzen, Stuttgart, 1890, p. 324. 



* Comes, Dr. O., Crittogamia Agraria, Naples, 1891, Vol. I, pp. 167,168. 



^Tubeuf, Dr. Karl Freiherr von, Pflanzenkrankheiten (lurch kryptoganie Para- 

 siten verursacht, Berlin, 1895, pp. 86, 87, and 184. 



^ Frank, Dr. A. B., Die Krankheiten der Pflanzen, second edition, Breslau, 

 1896, Bd. II, pp. 249, 250. 



■'Ehrenfels, J. M. Ritter von, Ueber die Krankheiten und Verletzungen der 

 Frucht- oder Gartenbiiume, Breslau, 1795, p. 225. 



