PREFACE 



THE aim of this book is to enable those directly occupied 

 in the cultivation of plants, and with but a limited period 

 of time available for study, to determine the nature of 

 diseases caused by parasites of vegetable origin ; to apply 

 in the most approved manner those curative and preven- 

 tive methods which experience has shown to be most 

 successful in combating the particular form of disease 

 under consideration ; and finally, to include in the daily 

 routine of work precautionary measures which, without 

 being costly, frequently prevent a slight disease from 

 assuming the proportions of an epidemic. 



Those desirous of obtaining fuller information respecting 

 the life-history of the parasites mentioned in this book, 

 also of others not included, can do so by consulting the 

 literature indicated under the different species. In con- 

 nection with this part of the subject, it may be well to 

 state definitely that success in the study of plant diseases, 

 or Vegetable Pathology, must necessarily be preceded by 

 a correct knowledge of the broad principles of the normal 

 mode of plant life, known as Vegetable Physiology ; and 



