CRANBERRY DISEASES 197 



berry Growers' Association at its meeting passed resolutions 

 out of which came a state law for the prevention of the spread 

 of fungous diseases of plants. This law included cranberry 

 gall. Since that time the disease seems to have been less 

 destructive, although it is doubtful whether this fact has any 

 connection with the legislation just mentioned. 



Symptoms. 



The first signs of gall appear about May first, and by July 

 first the disease is well advanced. As the name indicates, 

 galls are produced. They vary in shape, depending on the 

 part affected, although in general they are cup-shaped. They 

 measure from one-twenty-fifth to one-thirty-sixth of an inch 

 in thickness and length. The galls are found on young 

 stems and leaves and even on the flowers and fruit. Their 

 color is reddish, so that the disease has been called red-rust. 

 A badly infected plant presents in its entirety an unusually 

 red color. 



Cause. 



The gall disease is caused by a fungus, Synchytrium Vaccinii. 

 The pathogene is of a low order and possesses no mycelium. 

 Within each gall globose bodies, sporangia, are produced. And 

 within each sporangium a mass of swarm-spores develop in 

 the spring. The sporangia rupture and the spores are liberated. 

 The spores are motile and move about in water very easily ; 

 in fact, they are dependent on abundant moisture for their 

 dissemination. Possibly the fungus is carried from one place 

 to another through the air on the feet of birds, or by the wind. 

 It should be borne in mind that while the cranberry is an ever- 

 green, the other hosts, like azalea and huckleberry, are deciduous, 

 dropping their foliage which might drift for long distances 

 over the snow crusts in the winter. April floods spread the 

 fungus rapidly. Should it enter a bog at the head of a stream, 

 the fungus would quickly spread to all plants growing along 

 that stream below the point of entrance. 



