S3 



these spots are at first raised, aiiiiearing as small Imiwn lilistm-s (in the skiu 

 of the apple, aiul are frequeutl.v so arraiigeil as tn suf^gest that the points of 

 infection had followed drops of water tri(klin^' dnwn the sides of the apple, 

 the specks being distributed evenl.v over the upper or stem end. fnini which 

 the specked areas extend in strips toward the calyx end. 



When a number of spots appear on a single apple they soon cualesce. and 

 three or four gaining the ascendency, envelop the others and retain their 

 ciri'uhir slia))e. each producing its rings of fruiting pustules. Finally, the 

 entire fruit is converted into a dark-br<iwu shrivelled and wrinkled numuuy, 

 which m.-iy h,-ing on the tree a year or more. However, the majority of the 

 affected fruits fall to the ground before they are half rotten, .and their 

 decomposition is hastened by scavenger insects and decay fiuigi. 



Iiifliii iiiiinj CoiiditioiiH. 



Weather. — The preiloniinating conditions that influence the development 

 of bitter-rot are temperature ami humidity. .V few rays of hot. showery 

 weather may start an epidemic tb.-it will destroy the entire cro]! of certain 

 varieties, provided the fungus is present. 



Mdisturr. — Moisture is not only necessary for the germiimtion of the 

 spores, but it favours the growtli of the fungus and hastens siiore production. 

 In a moist atmosi>here the .sjiores are produced nuicli more ra]iidly than when 

 the air is dry. Moreover, rain is ;iu active agent in the spread of the disease, 

 splashing the spores from an infected apiile to ad.i'aci'ut licallliy fruits. 

 Heavy dews, followed b.v hot cloudy days witli a humid atmosplicre. ajipear 

 to make ideal conditions for the rapid develoimient of this disease. 



('(iiiclllsidii.i ami h'rcdiiniii inhitiijiix. 



Sunnnarising the results obtained, and considering tlie fact that the experi- 

 ments were made during a season luuisuall.v favourable to bitter-rot. tlie 

 following conclusions ni.-iy lie drawn : — 



1. Bitter-rot c.-in be completel.v controlled by ]ii-oiier a|i|ilicat ions of I'xir- 

 deaux mixture. 'XiM to !)S.9 per cent, of sound fruit liaving been s.aved b.v such 

 treatment in these experiments, while the checks rotted c'om|ilet<'ly. 



L'. Four aplilications. when ni;ide ,iust at the right time, are sulticient to 

 control the disease satisfactorily, but in order to Ite sure of covering the 

 infection periods one or two additional aiipHc.-if ions amy be necessary. 



3. The applications shoidd be made at intervals of two weighs, lieginning 

 about six weeks after the trees bloom. 



4. It is neee.s.sary to .spray the trees thoroughly, co.iting the fruit on .-ill 

 sidi's witli flue mist-lilve applications. 



."i. Other diseases, such as scab, leaf-spot and sooty-lilolcli, may be con- 

 trolled in connection with the treatment of liitter-rot. 



For the treatment of bitter-rot alone, spray the trees thoroughly with 

 P.ordeaux nuxture at intervals of two weeks until live applications have been 

 m.ade. beginning not later than forty days after the petals have fallen. 



For the combined treatment of .apple scab and bitter-rot. spray the trees 

 thoroughly with Rordeaux mixture: (11 Just before they l)looni. hut after 

 the cluster buds have opened and exposed the flower buds: (2) As soon as 



