xvi Report of the Botanist. 



To the Botanist of the Cornell University Agricultural Experiment 

 Station. 



Sir : — 



During the past year a bulletin on " Some Important Pear 

 Diseases " has been published. This bulletin comprised, especially, 

 notes upon the leaf-spot of pear, another leaf fungus, probably often 

 confused with leaf-blight. Leaf-bHght, scab, and pear-bhght are also 

 discussed and illustrated. Spraying experiments demonstrated that 

 Bordeaux mixture may be effectually used to prevent the leaf-spot. 

 Other more obscure and less injurious pear fungi are under observation. 



Investigations upon a mold growth occurring upon the parchment 

 paper lining and upon the wood of butter tubs have determined the 

 conditions of growth of the fungus. Care in the selection of tubs 

 made from well-seasoned heart wood, the storing of tubs in a dry 

 place, and the use of the best parchment paper will probably reduce 

 the amount of mold. Experiments indicate that the use of one per 

 cent, formalin solution, or a very weak solution of copper sulphate on 

 the paper will prevent the growth of mold. These results were pub- 

 lished through the agricultural press. 



Onion fields are being closely observed for the appearance of the 

 disease known as ''onion blight." In regions frequently troubled 

 by this disease, preventive spraying experiments are now in progress. 



A rot of greenhouse tomatoes has been the subject of considerable 

 experimentation. No fungus has been found associated with the 

 disease, and the attempt is being made to ascertain, if possible, the 

 conditions which may induce it. 



The shot-hole fungus and the shot-hole effect on leaves of peaches, 

 plums and apricots have received some attention, and this work may 

 be completed during the present season. 



Field spraying experiments with the late blight of celery indicate 

 that Bordeaux mixture is effective for the prevention of the disease, 

 and that this fungicide may be used until within about five weeks of 

 bleaching. 



Studies upon some " damping off " fungi are in progress. An effort 

 is also being made to look more carefully into the subject of the bacterial 

 diseases of plants. 



Very respectfully submitted, 



B. M. DUGGAR. 



