50 Report of the Director. 



the mushroom substance is properly " diluted " with sterile sand and 

 the plants make a more healthy gro"v\i:h and more increase in plant 

 substance than those grown in sterile sand alone. These experiments 

 will be continued. 



3. Investigations have been started to determine the life-history 

 of several parasitic fungi affecting fruits and vegetables for the 

 primary purpose of determining the perfect stage of development and 

 the manner in which the fungi exist during the winter. 



GENERAL WORK. 



Aside from the special problems for investigation there is a great 

 deal of work which is of a general character. Tliis consists of observa- 

 tions, notes, photographs, etc., of a great variety of plant diseases 

 caused by fungi. The work is done for the purpose of accumulating 

 data which will be of value in replying to the numerous calls for 

 information which are received and also will serve in many cases as 

 the basis or aid in some future piece of investigation. Much time is 

 also required to attend to the large correspondence, to determine 

 plants sent in for determination, to name fungi and fungus diseases, 

 and to recommend methods of treatment for fungus diseases, etc., etc. 



I would also call your attention again to the need of a special 

 building for the study of plant diseases as outlined in my last report. 



EXTENSION WORK. 



This work has been prosecuted with unusual vigor and success by 

 the plant pathologist, Mr. H. H. Whetzel, whose report is given here 

 for the year ending September 30, 1905 (comprising remainder of this 

 report) : 



The following is a brief statement of the chief lines of investigation 

 carried on during the year. 



1. Blight canker of apple trees.- — Investigation into the nature 

 and cause of certain cankers of young apple trees was begun in the 

 autumn of 1904 and has been continued up to the present time. A 

 very large proportion of the time and funds at the disposal of the 

 pathologist have been devoted to the investigation of this disease. 

 The work has consisted of trips to various parts of the state where 

 the disease was known to be prevalent and severe, for the purpose of 

 studying the trouble in the field. An orchard of 350 apple trees near 

 Ithaca known to be slightly affected has been visited weekly, and a care- 

 ful record of the condition of each tree made every two weeks with the 

 object of collecting data on the different stages in the progress of the 

 disease, methods of dissemination, susceptibility of varieties, etc. 



