420 Report of tke Horticulturist of the 



same dcscrii)tion of gross characters and the same lines of treat- 

 ment will apply to both. For description and treatment, see 

 -"JPlum hlack knot," page 452. 



FRtJit ROT. 



(Monilia fructigena P.) 



Description. — The rotting of the ripening fruit on the tree 

 often causes great injury to the crops of cherries, plums, apricots 

 and peaches. A fungous parasite attacks the fruit and causes it 

 to rot. The same fungus under favorable conditions, especially 

 when the ^vcather is warm and moist, and the growing shoots are 

 tender and succulent, may attack the ends of the twigs and also 

 the blossoms. Frequently the rotted fruit remains on the tree 

 over winter in a mummied form and the following season, under 

 favorable weather conditions, becomes covered with spores by 

 means of which the disease is propagated. These mummied fruits, 

 therefore, should be collected and destroyed before growth starts 

 in spring, as a preventive of infection. 



The fungus sometimes does considerable damage by destroying 

 the blossoms, but usually it causes most loss by attacking the 

 fruit. It occurs on unripe fruits, but usually spreads most rapidly 

 and does most damage when the fruits are nearly or quite ripe, 

 ■especially if they hang in clusters or touch each other. Under 

 weather conditions very favorable to its growth it may practically 

 ruin the ripening crop within a short time. 



Treatmeni. — The disease may be prevented to some extent by 

 treatment with fungicides, but it is extremely doubtful whether it 

 can be entirely controlled by spraying. Bordeaux mixture applied 

 soon after the fruit sets persists, to some extent, until the fruit 

 ripens and will show on the ripe fruit. The other mixtures which 

 have been tried are of doubtful utility, taking all things into con- 

 sideration. For both this disease and the leaf-spot it is suggested^^ 



15 Beach, S. A. N. Y. Agr. Exp. Sta. Bui. 117: 134. 



